By Ernie Rezents ISA Certified Arborist,
and ASCA Registered Consulting Arborist—
articles in June 12, June 26, July 10, and July 24, 1994 will provide you with much information.Successful Gardening to You.
By Ernie Rezents ISA Certified Arborist,
and ASCA Registered Consulting Arborist—
By ERNIE REZENTS
For The Maui News—
The first papayas, Carica papaya, were disseminated worldwide by the Spanish and Portuguese sailors from the lowlands of Central and South America. Papayas were introduced into Hawaii in about 1820. These were the large fruited type. In 1911 the “solo” variety was introduced from Jamaica by the University of Hawaii and today it is the only type that is grown commercially. Papayas grown in Hawaii today have undergone major improvement through hybridizing and selection for desirable characteristics.
Both green and ripe papaya fruit supply a very large amount of the vitamin C we need in our daily diet. The ripe fruit is a good source of carotene which the body converts into vitamin A. Papaya is a good source of potassium as well. So it doesn’t only taste good, but it is good for you.
Popular solo papaya cultivars.
People often ask for plants of the “low bearing” type to make it easier to pick the fruit. This expression means that fruit will develop low on the trunk. However, these trees will eventually grow tall and bear fruit high above the ground. It will then be time for tree replacement.
Popular cultivars are:
‘Sunrise‘, or strawberry papaya, has a reddish-orange flesh. It is excellent in taste and has a relatively soft flesh when ripe. Because it bruises easily when ripe, it has a shorter shelf life than some other types. This is a very popular fruit and is sold in most stores.
‘Sunset’ is a new hybrid solo papaya with salmon-pink flesh. The fruit averages about 15% smaller than ‘Sunrise’; it has a firmer flesh than ‘Sunrise’, and has a longer shelf life. ‘Sunset’ plants are low bearing, producing the first fruits at about 32 inches above ground level. The trees produce the first fruits about 10 months after planting. There is little or no flower sterility and the flesh is without lumps and stringiness.
‘Kapoho‘ is a solo strain with fruit about the size of ‘Sunrise’. It is a firm fruit that is ideal for shipment and was developed for planting in Kapoho, Hawaii, where the rainfall is 100 inches a year and the “soil” is Aa lava. If it is planted in dry areas the fruit becomes exceptionally small.
‘Waimanalo‘ low-bearing, or ‘X-77’, is a solo strain that has large fruit with a short neck (more oval rather than shaped like a light bulb). The first flowers appear about 32 inches above ground. The firm flesh is orange-yellow in color, and should be eaten when fully ripe otherwise it might be difficult to spoon. It ships well because it does not bruise so easily.
‘Filipino type‘, or large fruiting types, is a delight to grow because of their sheer size. During high light times of the year they are sweet and at other times they are “so-so”. As a kid we had the watermelon papaya. It was about 15 inches long and about 8 inches in diameter. It had pink colored flesh; at the time we thought it tasted quite good. I have a large fruited, orange fleshed, low bearing, Filipino type papaya at home but it doesn’t come close to having the ‘Sunrise’ papaya fruit quality. The large types are good when cooked green as a squash in dishes such as Chicken and Papaya.
Papaya plants are usually started from seed and planted either in pots or directly in the ground. The seeds should be saved from productive trees with good tasting, well shaped fruit. Preferably one that is not summer sterile- no fruit produced due to female sterility when it is warm. Select from the best! The seed’s gelatinous envelopes should be washed off because it inhibits germination. About 5 seeds are planted in a pot and 10 seeds at a field site. Dried seeds can be kept in the refrigerator for planting later, but I have found that germination is best with fresh seed.
After germination, keep the two or three strongest plants that are separated from each other. Pinch the others out at soil level. Seeds will produce about two thirds hermaphroditic plants and one third female plants. Male plants are few and far between. The two or three plants growing in a pot should be planted in the same hole. The multiple plants per site is to facilitate selection of a plant bearing hermaphroditic flowers and eliminating all others. If all your selected plants have hermaphroditic flowers, the strongest plant is kept and the others are sacrificed. The plants should flower in about six months for you to make this selection.
The Papaya Flower.
If you have papayas in your yard, collect a flower and locate the parts as described here. The hermaphroditic flower has both male and female parts in one flower. The five creamy-colored petals fuse at the top portion of a small papaya fruit (the ovary). At this union, each petal has 2 orange colored male parts (anthers-10 in all). The miniature papaya (ovary) is topped by a stigma with 5 horns. Flowers with less than 5 stigma horns will develop into elongated fruit; some even resembling cucumbers. Pollination occurs when insects transfer pollen from the male’s anthers to the female’s stigma. Fruit development follows. Unfortunately many hermaphroditic plants develop flowers that are female sterile during the summer heat. Summer sterile flowers resemble male flowers because the ovary is extremely tiny and not available for pollination. When checking the plant’s trunk you find a cluster of fruit, then a section without fruit, and then the top-most section has young flowers and small developing fruit. The section without fruit is from the time that “summer sterility” occurred. Opening up a summer sterile flower reveals an undeveloped ovary that is needle shaped and has no similarity to the miniature papaya ovary found in the normal flower.
Female flowers have five petals that remain separate and are attached to the base of the ovary. The ovary, again a large miniature papaya, has pronounced stigma horns at the top. Pollen needs to be transferred from either a hermaphroditic or a male flower to the stigma because of the absence of the male part. These fruits are rounder in shape, have a thinner flesh, and have few to no seeds, but taste the same as fruits from hermaphroditic flowers. The big advantage of having a female tree, along with hermaphroditic trees, is that it does not develop summer sterility and therefore bears more fruit during the winter.
Male flowers look just like the summer sterile hermaphroditic flowers (5 petals, 10 orange male anthers, but no central female ovary or miniature papaya). The flowers appear in clusters at the end of long stems. At times the plant’s hormones cause the female part to grow normal, pollination occurs, and a fruit is formed. You can recognize these trees because the fruit hangs from stems about 2 feet in length.
Commercially, female and male trees are eliminated and only trees with hermaphroditic flowers are kept. However, I have seen female trees in backyards tight with round shaped fruit. Pollen was transferred by insects from close by hermaphroditic plants.
Growing plants in aa lava is not my type of farming. Kapoho, on the Big-Island, has a high rainfall that is well distributed through-out the year. The aa lava is porous and provides excellent drainage. The warm weather, good sunlight, mild winds and use of slow release fertilizers, round out a good growing environment for papayas. Hence it is an area for commercial production of this fruit.
Tillable soils are my preference. Papayas prefer a well drained loamy soil with a pH of 5.5-6.7. Soils more acid than 5.0 will need to be limed. Wet clayey soils will stay wet longer and might lead to root fungal problems. But don’t despair; I have seen papayas growing in Haiku acidic soils. Raising your soil’s pH, planting on a slope, maximizing exposure to the sun, and encouraging wind circulation will help produce home-grown fruit.
What could be more fun than to have papaya for breakfast from your own yard?
Elevation and Temperature.
The temperature of an area influences the type of flowers and quality of fruits formed on a tree. A decrease in temperature results in a decrease of fruit quality. If temperatures are between 60 and 76oF for very long, 99% of the fruit may be deformed while only 12% of the fruit may be deformed if the temperature is between 70 and 81oF.
Papayas will grow up to 4,000 feet elevation. Above 1500 feet, the quality decreases. Best quality fruit is produced below 900 feet in elevation. High elevations produce fruit with hard flesh and low sugar content. So papayas recommended for one area may not do well in another if the growing conditions are different. For home gardeners who live below 900 ft elevation, the Sunrise, Sunset, and Waimanalo cultivars will do well.
I will continue with part II next time. Thank you for the many favorable comments I’ve received. I hope the past 31 articles have helped you become more successful gardeners.
By ERNIE REZENTS
For The Maui News—
I haven’t met a person who did not like to eat bananas. It can be eaten any time of the day and be prepared in many different ways. One of my favorite lunches is a peanut butter sandwich containing a banana sliced lengthwise. One sandwich will “stick to your ribs” all day. One needs to be creative to use home-grown bananas because it is either feast or famine. Neighbors and relatives benefit; drying preserves them for future snacks. Our favorite is the ‘Brazilian Banana’. A peeled Brazilian weighing 100 grams, contains 118 calories, mostly from carbohydrates, vitamins A, B, and C, calcium, phosphorous, iron, protein and 370 mg of potassium, which is 15 % of an adult’s recommended daily allowance.
Have you seen what bananas sell for in the store? At times one bluefield banana costs about 42 cents. Those with yard space could easily plant one or two plants.
There are three major groups of dessert bananas, Musa acuminata:
Cooking Bananas or Plantains, Musa balbisiana.
There are many different types of “Cooking” bananas. The fruit are usually short, fat, and starchy. Cut them in halves, pan fry in a little butter, and sprinkle them with a little brown sugar. You can also fry ripe dessert bananas; they become mushy-soft and very sweet.
The Cuban Red banana is an exception because it can be either cooked or eaten raw when ripe. It is a beautiful tree because the trunk, leaf petioles and midribs are dull red in color. The fruit ripens from red to yellowish red. The plants grow to about 20 feet tall and are tolerant to Panama Wilt and burrowing nematodes. If anyone has a Cuban Red Banana plant with a bunch of large red fruit, call me at my office (242-1285). I would like to photograph it.
There is a variegated form of the cooking banana. Both the leaves and peel have white streaks. Some of the bananas growing in the wild have seeds. Fortunately for us the ones we eat do not develop seeds.
I grow the ‘Chinese’ banana – doing very poorly due to shade, ‘Brazilian’ (dwarf-apple) – excellent production, ‘Williams’ – fruiting well, ‘Cuban Red’ – new plant, and a novelty called ‘Hapai Banana’. The book, In Gardens of Hawaii, describes this particular banana as a curious form that “bears small fruits which mature within the trunk”. The trunk is supposed to become swollen and ruptures for harvesting. The plant has the appearance of being pregnant. A friend gave me a plant, and it recently had its first bunch. Much to my sorrow, it did not develop the swollen trunk but produced the bunch out the top, the normal way. I guess it must be on the “pill”. The fruit tasted like the ‘Williams’ but did not have much shelf life. Maybe the environmental conditions affected the tree’s “birthing”.
The ‘Brazilian’ bananas sell for higher price in the store. They are not bland in taste and have a long shelf life. My bunches have as many as 13 hands.
I wanted to expose you to the more common banana cultivars so that you can select those that meet your requirements. Before deciding, read the next articles because they will deal with planting, caring, harvesting, pests and diseases. Meanwhile, buy some of the different types of fruit from the store and give them the taste test. Try some of the cooking cultivars. Consult a local cook book for ideas.
By ERNIE REZENTS
For The Maui News—
It seems that avocados are in abundance because we have been offered several different types for consumption. I am a firm believer that there are basically two types of avocado trees. One type should be planted in gulches because it grows too large and the other is small enough to be planted in a residential lot. With lot sizes decreasing, dwarf or medium sized trees are popular.
The avocado, Persea Americana a, is among the earliest of fruit trees to have been brought to Hawaii. It was introduced by Don Marin and by 1855 was quite common on Oahu and was being planted on the neighbor islands as well.
There are three races. The Mexican race, which the Fuerte variety belongs to, is grown to a limited extent. The West Indian is known as the “summer pear” because it fruits primarily during that time of year. It has a seed that fits loosely in its cavity. The Guatemalan fruits from fall to spring and is called the alligator pear because it has thick, hard, and often rough skin. The seed fits tightly in the cavity. Determining the race of your favorite avocado may be difficult because they cross pollinate and produce seeds that when planted grow into trees bearing a mixture of characteristics.
I judge the quality of an avocado by its taste. I like fruit that is somewhat drier and nutty in taste. It should have a thick flesh and a small seed. Peeling easily is an advantage for slicing. Otherwise a spoon or knife will be needed to separate the fruit from the rind. Some types hold onto their seeds tightly like the Hass does, while others shed their seeds easily but leave a brown skin on the flesh. I would prefer one that has a loose seed that falls out of its cavity brown skin and all. I like small to medium sized trees to facilitate picking and prefer to have year-round production. One tree will usually not provide all the traits a person desires, especially the year round production. Read on to learn how I achieved the impossible.
The avocado’s sex life is intriguing. There are two types based on when the female flower part is receptive and when the male [art is shedding pollen. In the “A” type the female flower part, the pistil, is receptive in the morning. The male flower part, the stamen, sheds pollen on the afternoon of the next day. Ion the “B” type the female flower part, the pistil is receptive in the afternoon but the male flower part, the stamen sheds its pollen during the morning of the following day. So the female and male flower parts within a type “A” or “B” tree are not ready at the same time. They are incompatible. When she is willing, he is not available. When he is “ripe” with pollen, she has already had her fling” The trees solve this incompatibility by obtaining pollen from each other. Flies, bees, and other insects transfer pollen from type B to “A” in the morning and from A” to “B” in the afternoon.
I inspected the avocado trees in my yard and found one type B, the Fuerte, and three type “A”s: Little Cado, Hass, and a graft I call “Miki”. When the female part (pistil) is receptive, it stands straight up and is in plain view. When the stamens are producing pollen the female part is surrounded by 3 “oar-like” appendages. The stamens then become fully exposed to insects. This physical change occurs within the flower around noon. To verify this, check your trees when they are in flower next time.
There are enough type “A” and type “B” trees in your neighborhood to insure pollination of your avocado flowers by insects. I wanted to guarantee this so I grafted a root stock with both Hass, type “A” and Fuerte, type “B”. I call this my “incestuous” tree. The disadvantage of this arrangement is that I must maintain two separate trunks and the Fuerte is a slightly larger tree than the Hass. The Fuerte needs to be on the north side and the Hass on the south to maximize sunlight exposure. Neither of these trees are a dwarf so height adjustments will be needed later on. The fruiting season for Fuerte is from November to June while the Hass is February to October. So I will just about achieve avocados all year round with one tree containing two grafts. A drawback is that Fuerte bears on alternate years. I have just one fruit this year. I had many last year. Hass is consistently a good bearer. It has small immature fruit as well as fruit that are being picked for eating.
The take home message from the avocado sex life is every seed has characteristics from two distinctly differently trees. The resulting seedling will bear fruit but its quality will be better, somewhat similar, or “junk” but never exactly the same as what you planted. It is better to invest in a grafted tree with known fruit quality than to chance it with a home-grown seedling.
Some popular varieties with their flower types and bearing seasons are:
Fall and Winter: Case (B), Kahaluu (B), Semil-34 (A), and San Miguel (A).
Winter & Spring: Greengold (A), Hayes (A), Nishikawa (B), Sharwil (B), Hass (A), and Fuerte (B).
Spring & Summer: Chang (B), Murashige (*B), Ohata (A), OHATSA (JA), ANAHEIM (A), Hass (A), and Little Cado (B).
Hass is a medium large tree and it bears small bumpy-skinned fruit. The rind turns purple when the fruit is ripe. Its oil content is 18% and is the largest commercially produced variety on the mainland. It is a heavy bearer.
The Fuerte grows into a large tree. The fruit is medium in size with a medium-thin green skin. The fruit oil content is 18 percent, and it is the second largest commercially produced variety on the mainland. It bears a good crop on alternate years. (True for my tree).
The Little Cado grows only eight to fifteen feet high. The fruit is medium in size with a medium-thin skin. The fruit oil content is 18 percent. It bears a good crop on alternate years. If all the fruit is picked by December 1st, flowering will occur in the spring for yearly fruiting. (True for my friend’s tree.) This is a good bearer.
Anaheim is a small to average-size tree. The fruit is medium to large in size and contains 10-12 percent oil. Its bearing capacity is fair. Whitsell is such a small tree it develops several leaders. It beavers medium sized fruit with an oil content of 18 percent. It is a heavy bearer for its size. They are short and sparingly looking. I think it looks ugly.
Greengold is a medium sized tree (about 20 feet tall), bears medium size with a green skin. My guess is that its oil content is equivalent to the Hass (18 percent). It is excellent in taste. I have been told that it bears on alternate years. A person should experiment and pick all the fruit by December 1st to determine whether fruit is then produced yearly. This is the case with Little Cado. Fruit quality may not e as good when picked too early – less oil.
Greengold is a seedling of Sharwil.
Sharwil is very similar to Greengold but has fruit every year. It is Hawaii’s main commercially grown variety. It is excellent in taste and originated from Australia.
I would like to continue this next time and discuss avocado selection, planting, caring, and harvesting.
By ERNIE REZENTS
For The Maui News—
Two weeks ago I wrote about pruning hedges and young trees and mentioned some safety precautions a person should take. I cannot over emphasize that it may be cheaper and safer for you to hire a knowledgeable person to do major pruning for you than for you to do the job yourself. Young trees with branches less than 2 inches in diameter, roses, and hedges may be possible for you to prune safely. It has been said that if you need to get on a ladder to prune a tree it is time to call for the help of a professional. However, if you do know good pruning techniques discuss these with the individual you are about to hire. Make certain that your trees are not butchered. Climbing spikes and broadleafed trees don’t mix (See my article dated February 27, 1994). Make sure that the pruner is currently insured (call his agent) so that you are not liable. Inspect some of his recent work, and talk to these tree owners. The kind of work you require will dictate the skill needed by your pruner. Shop around and be selective.
Guiding Principles For Healthy Trees
Making the Cut
Heading Back, Stubbing, or Topping, are all names given to removing limbs away from their point of origin. “Stubs” or a “hat rack” results. The branches respond with a flush of weakly attached sprouts that convert the tree into a round bush (See Photo #1). If all the shoots are kept they will develop into branches that rub and interfere with each other. Because they are weakly attached, they may become a liability. This is especially true when they get big, support weights (fully leafed, wet from rain), and are exposed to strong winds. The larger the stubbed limb the more unlikely the branches will ever grow to a size where the wound is completely healed and hidden by being incorporated in the growth of a dominant limb. Good examples are the once beautiful trees that line Puunene Avenue traveling towards HC&S mill (Photo # 2). Some of the monkeypods that were transplanted along sections of Hana Highway are candidates for a similar fate.
Thinning Cuts are preferred. These remove a lateral at its origin just outside the branch collar. Leaving the collar, or rings, intact will assist in the formation of callus and wound healing. Three cuts are required. The first should be about 12 inches away from the branch collar, cut from the bottom up and at least one third of the way through. The second should be about 3 or 4 inches away from the first, cutting from the top and going right through the branch. The third and final cut should be outside of the branch collar. (See Figure # 1). Some people make a slight cut below the branch just outside the collar to prevent tearing the bark when the third cut is made.
If the cut is made into or too close to the branch collar, callus and wound healing will be uneven.
Lowering the Height of Trees.
Trees are often “topped” to shorten them. If a smaller type tree were planted initially, the topping would not be necessary. Trees can be shortened by “drop crotching”. Remove the top with the customary first and second cuts used in a “thinning cut” above the lateral you want to develop into the new leader. Then make the third cut. Some decay will result at the top, but hopefully the tree will wall this off and prevent its spread and the lateral branch’s growth will encompass and hide the injury.
I hope you have benefited from this article because “Once you have tamed a tree you are forever responsible for it”. This quote, or something like it, is from Dr. Alex L. Shigo He retired from the U.S. Forest Service as Chief Scientist and Project Leader on the Discoloration and Decay in Forest Trees. I had the distinct privilege of studying under his tutelage, along with about 23 other individuals, for four days in May 1992. My thanks to the Maui Outdoor Circle for sponsoring my attendance.
By ERNIE REZENTS
For The Maui News—
Most people are interested in pruning their plants properly and will find volumes written on the subject. Bookstores, libraries, journals and magazines are good sources of information. For the most part people can do their own pruning of shrubs and small trees. When you need to use a ladder to prune a tree, this is where it becomes more dangerous. A branch can fall and knock the ladder from under you. Also using a four legged step ladder is not as safe as a three legged orchard ladder. I speak from experience. A four legged ladder I was using, walked while I was about 8 feet above the ground. I jumped onto nearby grass but fractured my right forearm in 5 or 6 places. The therapy was many times worse than the injury. All is well now. I have full use of my arm and am a lot wiser.
This episode prompted me to go in with about three other persons and we brought in orchard ladders from the mainland. The freight for a single ladder was about the same as for the four. If you are interested in an orchard ladder, I suggest you inquire at a hardware store first. If you cannot find what you want on Maui, write to: Tallman Ladders, Inc.; 1460 Tucker Road; Hood River, Oregon 97031 (Telephone: (503) 386 2733). Ask them to send you their literature and price list.
We have a 10 foot one at the College, and I have a 12 foot one at home. The taller one is 5 feet wider at the base (50 inches) and 5 pounds heavier (29 lbs.). The tall one is good for picking fruit and doing maintenance on the upper branches of my trees, but it is clumsier and more difficult to maneuver. These ladders are listed from 6 feet to 16 feet tall. They are safer, but you must still use common sense. They will tip over if you place your center of gravity outside the ladder’s base. I am sure there are other brands, but this is the one I am familiar with.
A small book could be written on safe use of pruning tools such as chain saws. I will not get into this subject because the manufacturer’s manual does a good job. A bow saw, lopping shears, or pruning snips (depending on the size of the job) are safer but more work to use. I have tremendous respect for the chain saw and always use ear, hand, face, and head protection.
If the pruning job is too big, hire a person to do the pruning for you. It is worth the money. I have hired tree trimmers and asked that no spikes be used on the broadleafed trees. I did not want to create trunk injuries that could lead to fungal infections. The pruner used a bucket truck or “cherry picker” to get up into the branches to do his pruning. Palms, such as Coconuts, have a different arrangement of internal conducting tubes. Spikes will cause trunk injuries, but these are more isolated and may not affect as much internal material. I would suggest that the climbing spikes and hand tools be cleaned between trees, especially if disease is suspected. Use soap and water. I have even used a propane torch to clean my loppers and bow saw after pruning a virus infected citrus tree. Viruses may survive soap and water, but heat is more guaranteed. It is not necessary to melt your tools and the heat will probably cause your saw to lose some of its sharpness. Warm them with a torch and let them cool. Clean but do not torch gas or electric powered tools. Just hand tools and spikes.
Annuals, such as Petunias, can be pinched (tip pruned) to encouragebushy growth and additional flower production. Removing old flowers will prolong the annual’s life because seed production is a “sink” for energy. Luckily, most annuals develop a bushy appearance without pinching. Because of our great Hawaiian weather, some annuals live for several years. A good example is the periwinkle. Even though it behaves like a perennial, it does not need to be pruned.
The woody perennials, plants that live and flower for more than one year e.g. Hibiscus, mock orange, and trees, will require pruning. Without proper pruning they will grow out of control. Where you want to create a barrier, have unlimited space, or want to create a specific impression, an out of control growth is permissible. But for the most part, pruning will be necessary.
Hibiscus, mock orange, blue plumbago, etc. hedges should be pruned to encourage lower branch growth. Lack of light makes for sparse growth. The solution is to trim the hedge in a trapezoid shape the top narrower than the bottom so that both sides receive light as the sun travels across the sky. Most hedges are trimmed to resemble a rectangle. The sides receive less sunlight and develop weak growth.
A very young hedge will need to be tip pruned to encourage lateral growth and develop fullness.
When is the best time to prune? Someone I knew used to say, “Whenever the saw is sharp”. This is not true. You can do minor pruning anytime of the year, but it is better to do major pruning when a tree is in either full leaf or no leaf. The worst time is when a tree is going through a transition losing, or putting on new, leaves.
Evergreen trees such as conifers don’t have a major leaf drop but drop leaves all year long. However, they do go through a resting stage during the winter and a flush of growth during the spring. So their best times sound like during winter and summer. In pruning conifers it is recommended that you maintain green growth on the branches as bare wood does not always sprout new growth and may die.
Prune the least amount possible for a better selection later. Branches left on the tree will feed it. A well fed tree will develop stronger roots and trunk and be much healthier. When transplanting it may be necessary to do limited selective thinning to decrease wind resistance. As the young tree grows taller maintain a dominant
or strong leader. Tip prune laterals that compete for dominance with the leader. If they are left on the tree, they will continue to feed the tree for better growth. Remove them if they interfere with traffic. In selecting which branches to keep, wide angled branches are much strongly attached than those emerging from the trunk at a narrow angle. The narrow angled branches may be torn off in strong winds.
I will continue with pruning older trees next time and how to make correct cuts.
By ERNIE REZENTS
For The Maui News—
Condominiums are some of the worst offenders, and it is usually done in-house without the benefit of a trained Arborist. Businesses and shopping centers with parking lots are probably a close second. Check out some of the stores along Alamaha Avenue in the Kahului Industrial Park for some good examples. Homeowners see it done so often that they accept and request that their trees be pruned the same way.
State highway and County park crews have been given instruction on correct pruning procedures within the last two years. New employees will need similar training. Now we need to get their private contractors to abide by acceptable standards, especially when it comes to libraries and schools and jobs too big for in-house pruning. Government should update bidding specifications by consulting with the Maui County Arborist Committee (243-7325) and realize that the lowest bid may cost them more in the long run.
What is Topping, Stubbing, Tipping, or Heading-back?
Why is it wrong to top a tree?
Why are trees Topped?
Corrective Action after Tree Topping.
Parking Lot Shade Trees.
If a tree has to be topped for whatever reason, maybe it is the wrong tree for that spot. Some mainland pruners have told me their companies will thin out trees, remove dead wood, raise or lower crowns, and if necessary remove trees, but they will not top them.
Maui’s world class hotels spend a lot of money planting and caring for their trees because they know trees provide cooling shade and beauty their guests enjoy. Improper pruning costs more money in the long run. Don’t accept it!
By ERNIE REZENTS
For The Maui News—
In my last article I focused on mango cultivars recommended for Hawaii and how the Rapoza and Fairchild mangoes should be planted in areas where rain and high humidity are normal during flowering time. I also said that I was not aware of a dwarf mango tree, well one of the nurseries I visited said that there is such a plant. The dwarf mango’s name was one I had not heard before and the salesperson did not know the fruit’s characteristics.
The mangoes we typically grow are not true when planted from seed. Only seeds of the polyembryonic type mangoes (those that produce more than one plant from a single seed) will produce plants that are true to the mother plant – common mango, Paris, Julie, Shibata, Kurashige, and No. 9 or Chinese mango. Therefore to obtain a young tree that is true to its mother, propagation needs to be made vegetatively by using a piece of the mother tree you want to duplicate. Grafting is the most common form of vegetative propagation of mangoes.
Even though cutting and air layering are methods of vegetative propagation mangoes are usually not propagated by these methods because of the resulting poor root system. In grafting, usually a seed of a monoembryonic mango is planted to serve as a root stock; when it has reached 3/8ths to 1/2 inch in diameter it is ready for grafting. A piece of the original tree is transferred to the root stock plant. It is this piece (the scion), bearing the genes of the desirable fruit tree, that will bear the name and fruit of your new tree.
Grafting techniques used are the side-tongue graft, side-wedge, splice, and cleft. A Honolulu propagator uses the approach or inarch method. In this method both stock and scion plants are on their own roots at the time of grafting. This requires that the mother tree have very low branches and young stock plants be raised to make contact with mother tree branches to be used in grafting. Both the mother tree and stock plant are given a tangential side cut and spliced together. Ties to hold the two together are usually nurseryman’s tape or raffia. For those wanting to do grafting, check how these methods are pictured and discussed in the library copy of Plant Propagation Principles and Practices by Hartmann, Kester, and Davies or some other reference. For the rest of us, buying a grafted tree from the nursery is easier and more guaranteed. Request the cultivar you desire and they will most likely be able to order it from the propagator. Grafted trees are usually shorter and bear mangoes from 3-5 years. Seedling trees usually bear in 5-7 years.
Planting and Watering.
Matured mango trees may occupy a space measuring 30 feet high by 30 feet wide. So check on overhead wires, underground pipes and utilities, buildings, and neighboring trees. The tree is kind of messy so plant it where leaf drop can be tolerated. Production will be better if the tree is in full sun and has some kind of a wind break – from a building or other trees. Most of the cultivars suggested for Hawaii will do better if planted in drier parts of the island so select your cultivar wisely. Dig a hole much larger and deeper than the container the young grafted tree is growing in. Some compost can be mixed in with the soil along with about 1/4th pound of fertilizer such as 16-16-16 . Do not overuse commercial compost made with sewage sludge due to possible burning. Even though the bag suggests one part compost to one part soil I would use one part compost to two parts soil at the most. Several persons told me that their trees died from using too much of a good thing. They exceeded the bag’s recommendation. Homemade compost without manure is safe, but I would still use it at the same ratio. Thoroughly mix the compost and fertilizer with the loosened soil and return enough soil to the hole so that the plant ends up growing at the same depth it was while in the container.
Remove the young tree from the container or mulch bag. Some people say that planting with the container will “force” the roots deeper. Containers restrict root growth. Loosening and amending the soil with organic material will encourage deeper rooting because oxygen and water can penetrate the soil more deeply. Because compacted soils limit air penetration roots grow nearer to the surface to obtain the required oxygen.
At the time of planting loosen the outer roots of the root ball gently to encourage outward and discourage circling growth. Plant the tree; firm the dry soil as you add it to the hole, but not to the point that air penetration is restricted. If you firm moistened soil it will compact and severely limit air penetration. Create a watering basin and water immediately. Add organic mulch/compost to the top soil but keep it away from the young tree’s bark. Water every 2 or 3 days depending on the season and soil type. After the first year, once a week watering may be sufficient. Matured trees need periodic watering especially if they are growing in a sandy soil or if there has been no rain. The planting technique described here can be used when planting all types of trees.
I think most of us do not use enough fertilizers yet we expect our trees to bear “bumper” crops. When we do fertilize we might over apply because we were negligent previously and try to make up. The amount of fertilizer you use will depend on the age of the tree, its health, and whether it is a heavy bearer. You can apply one pound the first year: one fourth pound at planting, another fourth after four months, and a half a pound at the end of 12 months. During the second, third, fourth, and fifth years apply two, three, four, and five pounds to match the age of the tree. Divide the amount into three or four portions and apply during the year. Mark this on a calendar so that you do not forget. Thereafter apply one pound of fertilizer per inch trunk diameter. Measure the trunk’s diameter at six inches above ground if the tree is smaller than four inches in diameter. If the tree is between four and eight inches in diameter measure the diameter at 12 inches above ground. For matured trees greater than eight inches in diameter, determine the trunk diameter at 54 inches above ground or just below where the trunk branches out (for a low branching tree).
When the tree is bearing fruit, divide the fertilizer to apply one half just before flowering and one half just after the crop has been harvested. Broadcast the fertilizer uniformly from the trunk out to the drip line and a little beyond. Water immediately and as needed thereafter to make the nutrients available to the tree.
Use fertilizers with a ratio such as 1:1:1 (15-15-15) or 1:2:2 (10-20-20).
Diseases and Insects.
Anthracnose, Colletotrichum gloeosporioides, is a dark colored fungus affecting flowers but more so fruit. Fruit with black spots on the rind most likely have anthracnose. Powdery mildew, Oidium mangiferae is a white (darkening to gray) fungus that affects leaves, flowers, and young fruit. It usually causes new leafy growth to twist, curl, and develop dark colored dead tissue. Flower clusters look gray and the fungus is easily seen. Both fungi will cause flowers and young fruit to drop. Sooty mold is a black fungus that is usually found on leaves infested with scales. Scales give off honey dew that the fungus lives off. Eliminating the scales by spraying Volck or agriculture fine oil is the answer. Scales, aphids, white flies, and mealybugs all exude honeydew on leaves and fruit which may lead to a black sooty mold problem. The recommended oil treatment is good for gardenias, citrus, etc., wherever sooty mold is a problem. Read and follow the directions listed on the container.
To cure powdery mildew apply one tablespoon baking soda with one tablespoon of Volck or agriculture fine oil per gallon of water. Spray the mixture on leaves and flowers on a weekly basis beginning when flowers first appear and until the small fruit have set. Apply Benlate or Benomyl, a commercial fungicide to control both powdery mildew and anthracnose. Two pounds of this fungicide can be purchased from United Horticulture Supply on Papa Place in Kahului (871-2622) . If smaller amounts are found at other stores you can buy it from there. You need to take precautions when using all chemicals (read the label) and maybe spraying just the lower branches will provide you with enough mangoes.
My problem (and probably yours) is primarily powdery mildew. I can use the safer baking soda cure. Benlate is probably more effective, but for the homeowner it is more hazardous.
The Mediterranean and Oriental fruit flies are a problem at times. Garden shops sell baits (sex hormones) that are used to attract male flies to a container containing an insecticide to decrease the fruit fly population. The products are methyl eugenol for oriental fruit flies and medlure for the Mediterranean fruit flies. Hang the container with the chemicals on some other tree to attract the males away from, rather than to, the mango tree. There is also a yeast product (Stahley’s bait) that is mixed with an insecticide that both males and females eat and die. Pick up and dispose all fallen fruit. Fruit fly larvae pupate in the ground prior to emerging as adults. Burying fallen fruit is therefore not the solution.
Adult weevils lay eggs on small green fruit before it is half grown. The eggs hatch and the larvae burrow into the soft seed and remain there until becoming adults. After the fruit has ripened and the flesh decomposed the weevils bore their way out. People eating mangoes are unaware of seed weevils because there is no evidence of their presence.
Because of fruit flies and the mango seed weevil, mangoes cannot be shipped to the mainland. The State has experimented radiating Haden mangoes and has successfully controlled the pests without affecting the fruit. The radiation plant is located on the Big Island. Whether mangoes are treated for export is to be worked out. I think Hawaii can consume all the fruit we produce. Some areas where flies and weevils do not survive the harsh winters (like Canada) already import mangoes without a quarantine. However our pests do limit exports of fruit and controlling or eliminating them would really open up agriculture opportunities.
This is the fun part. I obtained mangoes from Frank Swan of Maui Meadows, Maui Tropical Plantation, and Yee’s orchard in Kihei. I photographed them and my wife and I sampled them for fiber content, taste, seed size, and skin color. The results are:
|Keitt||Firm, flattened||Yes||Tart side||Very flat||Red blush with yellow/green|
|Golden Glow*||Long, firm||Low||Excellent, juicy||Very flat||Yellow|
|Irwin||Long, flattened||Very low||Good, velvety,|
|Mapulehu||Large with a nipple||Yes||Stronger taste, tart, juicy||Average||Red/yellow|
|Swann**||Long, firm||Yes||Tart, juicy||Flat||Red/yellow (Beautiful)|
|Fairchild||Long||Yes||Stronger taste, juicy||Average||Yellow|
* Golden Glow is a Yee mango and plants are unavailable.
** Indian and the Swann mangoes belong to Frank Swann. He bought the plants from Mr. Singh (Kihei Gardens and Landscaping) in 1985.
Of course an annual bearing cultivar would be preferred and disease resistance needs to be considered. All of the above are probably sensitive to Powdery Mildew and Anthracnose and therefore will do better in hot dry areas. Rapoza and Fairchild are recommended for wetter parts of the islands. I have not tasted Rapoza or the Gouveia mangoes yet. Gouveia is supposed to be the best tasting mango and is recommended for growing in hot dry areas.
Next time I will write about present unusual garden happenings. Are they due to El Nino?
By ERNIE REZENTS
For The Maui News—
Mango is enjoyed by many people but is grown only in tropical and subtropical climates world wide. India alone has about 500 different types and is this fruit’s major exporter. The Philippines is second. The main importers of mango fruit are England and France. Indians living in England and the British who formerly lived in India are the primary consumers of mango in England. As a kid I used to look forward to eating green and half green common mangoes dipped in a combination of black pepper and shoyu. We also partially dried half ripe mangoes that were cut right through the seed in halves then cooked them with Chinese Five Spice to make mango seed. We pickled half ripe mango flesh in sugared vinegar seasoned with Li Hing Mui seed and made pickled mango. We were envious of people who lived in Lahaina, or had friends living in Lahaina, because mangoes in that part of the island “came-in” earlier. Roadside stands sold (and still do) the early fruiting small type Lahaina mangoes. These fruit have a large seed, a somewhat stringy flesh, but are sweet tasting when ripe.
Even though I knew that Makawao is not mango country, I planted a Haden mango tree on October 1, 1972. The tree has been a poor bearer because invariably fungal diseases attacks the flowers. The tree still grows because it provides good shade. Haden mangoes do not do well in a wet humid environment because these are the conditions that promote the devastating Anthracnose fungus that infects flowers, fruit, and leaves. When infected, the leaves become discolored and crinkly. If a drought occurs during the time of flowering we can expect to eat mangoes that year. Luckily my father had a Haden mango tree in Wailuku that the family benefited from. When that source ended the entire family was not very happy. His tree was the only one producing mangoes for the family. Because this is the time for mangoes, and I have had many questions from people about mangoes, I will devote this and the next article to growing this popular fruit.
Mango, Mangifera indica, originated in southern Asia, especially eastern India and Burma. It is a member of the Anacardiaceae family. Other members of this family are: Christmas Berry, Cashew, Poison Ivy, and Poison oak. These plants contain chemicals that are toxic to many people. Some people can eat mango but must have someone else peel it for them. They are allergic to the sap and will break-out in a rash. Luckily most of us are immune to mango toxins so can peel and enjoy the fruit. I cannot say the same for cashew nuts other than those you buy in the bottle.
The mango tree grows in sandy as well as loam soils and requires good drainage. It will grow to 1500 feet elevation but is more productive if planted below 1200 feet and in areas that are dry during flowering. It requires less than 60 inches of rain per year but will need to have supplemental irrigation if it is too dry. I have not seen a dwarfed mango tree; the common mango grows to more than 60 feet tall. Most backyard varieties are between 25-40 feet tall. Creative pruning has dwarfed some to make picking easier and limits the amount of leaves dropped. Because trees are usually taller than commercial pickers, mangoes are commonly picked with a long bamboo pole with a hand fashioned stiff wire loop on the end to which a pant leg is sewn. The bottom of the pant leg is sewn shut to make a bag for catching mangoes. The stiff wire loop is crimped to create a neck large enough for the fruit’s stem to pass through but not the fruit. To pick a mango the bag is positioned so that the fruit is suspended within the bag. The fruit’s stem is passed through the crimped wire. The pole is pulled down. The stem snaps and the fruit drops into the homemade bag. Someone in Lahaina has a similar picker but only with a very long tube that reaches to the ground. Picked fruit move through the tube to the ground using friction to break its speed. The only problem is that the long tube would be difficult to pick mangoes from the tree’s interior. The bag is more convenient but requires frequent emptying.
The mango was introduced into Hawaii in about 1824 by Don Marin, a Spanish horticulturist in Honolulu, and the Reverend Joseph Goodrich, a missionary in Wailuku, Maui. Since 1903 the University of Hawaii Experiment Station has evaluated nearly 200 cultivars and has developed a list of types recommended for planting in Hawaii. Some not on the list are still a favorite to many of us for one reason or another. Many of the evaluated types were discarded because of poor production, inferior quality, unattractive color, and susceptibility to the Anthracnose fungus, Colletotrichum gloeosporioides. Resistance to or tolerance of the disease are important because conditions promoting an epidemic (rainy weather and high humidity) frequently occur during the flowering season.
Mangoes producing several plants from one seed are polyembryonic. These young plants (the common mango for example) are true to the mother plant. Most plants produce seeds that are monoembryonic – only one plant grows from each seed. These young plants are the result of sexual fertilization and because of genetics will not be true to the mother plant. The many recommended and not recommended mango cultivars are mostly of this type and are seedlings from known cultivars. Once a mango is selected and recommended for planting propagation must be by vegetative means, grafting primarily. Planting a seed does not provide you with the identical fruit.
The Haden mango is the most popular mango grown in Hawaii. It is a seedling of the ‘Mulgoba’ mango grown in Florida, 1902. The Haden served as a standard of excellence in Florida for many decades and when it was introduced into Hawaii was superior to any mangoes growing here at that time. The fruit is medium to large and has an attractive thick skin. The flesh is fibrous. Now with all the new cultivars to choose from the University of Hawaii is not recommending that Haden be planted. There are many other “newer” types that are superior in fruit quality and produce annually. The Haden produces a large crop in alternate years and is very sensitive to the Anthracnose fungus as well as powdery mildew. Mexico exports primarily Haden to the U.S. The cultivars described below are all part of the list recommended for planting in our State.
The Gouveia cultivar is named after a Mrs. Gouveia of Palolo Valley, Oahu. She planted a seed from the Pirie cultivar. The seedling tree produced good to excellent quality fruit (in fact the best quality compared to the other recommended cultivars). The Gouveia mango is sensitive to Anthracnose so should be planted in relatively dry areas. Its production is on the “light” side and bears fruit from July through August.
The Rapoza mango is another seedling and is named after Herbert Rapoza, a worker at the Poamoho Experimental Farm. This cultivar produces very large fruit, attractive in appearance, of excellent quality, and is generally late bearing (August through October). It bears a heavy yield each year. It flowers in the spring time and again later so is recommended for wet as well as dry areas. With the repeat flowering it produces fruit even though Anthracnose is a problem.
Ah Ping produces a medium sized fruit. This cultivar originated as a seedling growing in the yard of Mrs. Chu Ah Ping in Mapulehu, Molokai. The fruit’s appearance is excellent and quality very good. It is an annual bearer during June and July. Yield is of a moderate amount.
Fairchild was introduced to Hawaii from Panama by Walter Lindsey in the 1920s. It produces small yellow fruit of very good quality. It is tolerant of anthracnose and is recommended for wet humid areas. Its fruit is of very good quality and the tree produces a moderate yield. I have eaten Fairchild mangoes and can say that the fruit is not stringy and is of good taste. Because of its small size there is less to eat, but I would have had fruit all these years if I had planted a Fairchild instead of a Haden mango tree.
Pope mango is named for a horticulturist who worked for the experiment station. The tree is a seedling from one growing in Florida. It is consistently high-yielding and bears annually from July to August. Fruits are medium sized and rank second to Gouveia in taste quality.
Nam Doc Mai Mango is from Thailand. It is not on the University of Hawaii recommended list but is resistant/tolerant to Anthracnose. So is the Chinese mango that was so common many years ago. This latter mango is quite stringy, green skinned when ripe, and has a yellow flesh.
If I had to do it all over again I would plant a Rapoza mango tree. I am impressed with its characteristics; it can be planted either in wet or dry areas.
I will continue next time and will discuss propagation, planting, fertilizing, watering, and diseases.
By ERNIE REZENTS
For The Maui News—
When most people think of gardening they think of growing something to eat. This was even more apparent during my fall 1991 semester while teaching in Taiwan. Twenty million people on an island, high priced land, and large concentrations of people in cities and towns, made growing vegetables, rather than ornamentals, the preferred crop. Most non-farmers had small or no yards and bought their vegetables and fruits from stores and “farmer markets”. Some city dwellers grew fruit trees and vegetables on roof top terraces in tubs. Those who did not have a roof garden grew leafy cabbages and assorted greens on their balconies in containers filled with a hydroponic solution or soil. Ornamentals were on sale at nurseries to decorate homes. The wealthy could afford small yards landscaped with ornamentals and a few fruit trees with or without vegetables.
Many of us are fortunate to have yards to grow edible and ornamental plants while others have balconies that provide space for container gardening. It might be appropriate to write about growing vegetables before we delve into other sorts of plants.
The first thing you should consider is the site. Select an area with good sunlight.
Light is necessary for plants to produce their own food and grow in a healthy manner. During the summer, the garden should have full sun in a section for warm season vegetables and partial shade in another section for cool season (leafy) vegetables. Of course the summer and winter sunlight will be different in amount and direction so take that into consideration.
My main garden receives a half day or more of sun during the summer and slightly less during the winter. Be aware that small trees grow up to be big trees and may provide unwanted shade in the future. My garden provides evidence of this so nearby trees are pruned to control shading.
Your site should be close to a source of water so that hoses are convenient. A spigot is necessary even if you plan to use drip irrigation.
A site with good soil helps make for success. You can amend poor soil to improve it, but gardening is much easier if you are starting out with rich soil. Adding organic material such as manures and compost will improve the quality of your soil.
Wind is important for drying our wet plants and blowing away some pesty insects, but is it too strong? Do you need a wind break?
Is the area large enough for expansion if you want to get bigger?
When you have selected your site, remove the grass and weeds from the area. Digging, pulling, and maybe even the use of herbicides may be necessary. Healthy grass and weeds are more sensitive to herbicides, so you may need to water the area and apply your herbicide when regrowth occurs. Follow label directions and safety precautions.
After your soil is free of grass and weeds, dig it up thoroughly. The soil will be easier to dig if it is slightly moist. Of course a sandy soil will be “duck soup” while a clay soil will be sticky and difficult to work. After the soil has been softened, and before any soil amendments have been added, collect soil six to eight inches deep from the four corners and center of your plot and mix it up thoroughly. Remove two to three cups of this and take it to BEI in Wailuku, or HGP, or UHS in Kahului to be analyzed.
The soil test will cost you a few dollars but will include a complete determination of what is present and provide a recommendation of amendments to supply missing nutrients. The analysis will even suggest how to correct the soil’s pH.
If you wish, you can provide an edging around your garden with treated 2×4’s or 2x 6’s or do raised beds (2 feet. wide by eight to ten feet long). Think about how you will get into the garden for harvesting.
Balcony folks will have a limitation of space and therefore need to be more selective in what is planted and in what quantity. Because of their use of containers, weeding and digging will be minimized. It may not be worth the expense to have your soil tested but pH and available plant nutrients are still important. The pH can be maintained either by renewing the container soil periodically or through soil amendments. Nutrients can be provided through the use of organic matter or fertilizers.
So prepare your plot, or container, and next month we will get into the layout and planting your vegetables. Successful gardening to you.