Print this entry

Mark Christensen was elected as recipient of the NZ Tree Crops Association annual prize for contribution to Tree Cropping for 2006, the Dr Don McKenzie Award. This honours Mark’s outstanding recent research relating apples and cancer prevention. Mark’s contribution is to have tested the old heritage apples using science’s most modern analytical tool. No apple industry group or medical research science unit did this: Tree Crops did this, and set the whole scientific community ablaze. Mark has been contributing Apple (anti-cancer) articles to the Tree Cropper for over 6 years. His articles are printed in national magazines, and attract international scientific cooperation, and give a high profile to NZTCA.

Mark’s search for “apples against cancer” on the internet threw up the Finnish study that established a link between flavonoid compounds, mostly found in apples and the reduced incidence of major human diseases. Finns who eat an apple a day have the lowest cancer incidence in the world. Dr Lieu at Cornell University, USA, was investigating procyanidins to fight cancer. He achieved 49% kill of cancer cells in bowel cancer in mice. In cooperation with Hort Research at Massey Mark supplied 59 varieties to be tested on their High Performance Liquid Chromatogram. The heritage apples had up to 4 times as much flavonoids and procyanidins as commercial apples. No two apple varieties are the same – all test with different levels of compounds. There is a strength in maintaining diversity of apple cultivars within the country.

New Zealand apple growers have been persuaded over many years to remove old varieties and replace them with supposedly superior modern varieties. From a health aspect, this advice has been wrong. The outstanding varieties identified by this research are all seedling or heritage varieties. This proves the vital importance of maintaining a diverse gene pool of material, in apples as with all plant material.

The latest analysis of 125 apples from apple collectors all over the country has shown up Fuero Rous, a French cider apple, with an even higher proportion of procyanidins, flavonoids, anthocyanins. The French medical research team at Straussbourg University are concentrating on anthocyanins (the red colour pigments). Mark has supplied Monty’s Surprise apples to Cornell University, to Straussbourg University and to the Finns. An unexpected outcome from the original research was identifying a unique substance in Russet apples which slows the body’s absorption of sugar. This makes them suitable for diabetics. Samples were supplied to Massey University for the Diabetic Unit to follow up. A little known French cider apple called Fuero Rous has tested with the highest levels of procyanidins in the skin and flesh. This specialist cider apple variety has tested even higher than Monty’s Surprise, although Monty’s Surprise still has the highest levels for an eating apple. Given the nature of cider making and the fact that these cider varieties are not palatable, it would be difficult to develop a better use of these apples than cider (or cider vinegar), where all the benefits of these nutritional and medicinal compounds can be captured in a liquid form that for all intents and purposes should have powerful anti-cancer properties.

Consistent findings on the very high levels of compounds in seedling apple varieties, appears to indicate that the rootstock may have a much greater effect on the phytochemical composition of apple fruit, than has previously been considered. The implication from this is that to grow a tree to achieve the maximum health benefits from its fruit, it should be grown on its own roots. (It is possible that budding or grafting low to the ground, onto a rootstock, and then moulding or replanting above the graft union, may achieve the desired result – once the roots are established from the grafted scion, but this will need to be confirmed with further research.) Another factor to consider is the age of the tree. As a tree gains great maturity, (for instance 80 to 100 years), it appears to exhibit greater levels of compounds. This may in fact be a gradual process as the tree ages. The research data indicates that specific trees that are very old, test with high levels of compounds. Thus apple trees should be allowed to grow to a great age – to realise their full potential – (having been planted on their own roots in the first place!) Mark’s budget this year for research is $54,000.00. There are another 500 apple varieties to test. Thanks to Mark’s enthusiasm, members all over NZ are keen to grow the heritage apples identified so far.

Comparison of Top New Zealand Apple Cultivars against Commercially Grown Cultivars

Total Phenolics (a large group of compounds that in apples include flavonoids and phenolic acids. Phenolics are known to have beneficial effects on human health, including protecting against heart disease.)

Print this entry

Most plants can be propagated from cuttings however, some plants are quite difficult to persuade to grow roots, whilst others may take an inordinate length of time (years) to “strike”. Do not let such problems, either real or imagined, prevent you from trying. Propagating mix: Generally, sand, or vermiculite, or a mix of the two will be satisfactory. Even compost and/or composted wood-chips have been used with success.

Soft-Tip Cuttings: Usually taken in Spring. Very few fruit trees are propagated by this method, but generally anything in the Solanum group, such as Pepinos and Tamarillos will be fine. Take a reasonably substantial length (normally not less than 10cm) from the growing tip of the branch [twig]. Make the cut directly below a growth-bud. Remove all but the very top leaves, and reduce the size of the leaves which are left on, this reduces evaporation-loss of liquid from your cutting. Plant your cuttings in the propagating-mix to ¾ of its length. A rooting-hormone powder may be used, but is generally not necessary. Do not allow the propagating mix to dry out, and mist over the cuttings daily. Some method of supplying bottom-heat would be an advantage, such as sitting the container with the cuttings in the top of a hot-working compost heap. The cuttings may be potted-up as soon as the roots appear, often after only 3 weeks. Problems: Fungal infections resulting from the moist, humid conditions may require treatment with a fungicide.

Semi-Mature (Tip) Cuttings: Usually taken in Autumn. Citrus, Feijoa, and other evergreens can be propagated by this method. Note that many Citrus are prone  to soil-born diseases, and therefore only resistant varieties such as Poncirus trifoliata and citrange should be propagated by cuttings, usually for use as rootstocks. Take a reasonably substantial length (normally not less than 10cm) from the tip of a branch [twig] that has ceased its seasonal growth but is still green and soft. Make the cut directly below a growth-bud, or, if the propagating-wood is short enough, tear it off the main branch, leaving a “heel” of older wood attached. Remove all but the very top leaves, and reduce the size of those leaves, to reduce evaporation. Plant the cutting in the propagating mix to ¾ of its length. Do not allow the propagating mix to dry out. Some method of supplying bottom-heat is frequently an advantage. Commercial growers often heat the benches upon which the cutting trays are placed. The little plants should be rooted and ready to pot-up in Spring. Problems: Fungal infections are the worst danger, but watch out for snails and slugs.

Hardwood (Mature) Cuttings:  Usually taken in late Autumn or Winter. Deciduous fruit-trees can usually be grown by this method, but evergreens are also worth trying. Take a substantial length (normally not less than 15 cms long, or less than ½ cm thick). Make a slanting cut just above the terminal growth-bud, just as if you were pruning. Make a horizontal cut immediately below the bottom growth-bud on the cutting. Now you know which way is up, and you won’t plant the cutting upside-down! Remove any leaves. A slight vertical slit in the bottom of the cutting may increase the callous (rooting) area. Plant the cutting in the potting-mix to at least ¾ of its length (some propagators only leave the top bud above the surface). Rooting-hormone is generally a waste of money for hardwood cuttings. Do not allow the propagating mix to dry out. Some form of bottom-heat may help things along. The plants should be ready to pot-up by the following Winter. Some plants can take a very long time to produce roots: just put them back in and wait for another year!

Print this entry

The green sapote (Pouteria viride) tree grows very well in the Brisbane area as long as the soil is well drained. In marginal areas it is, like the avocado, very prone to root rot. The tree is an attractive one similar to the mamey sapote, but smaller. It originates from volcanic, mountainous regions of Central America, which is very well drained.

I recommend planting grafted of marcotted trees only in ideal conditions, otherwise plant seedlings. Hill the soil well if its condition is poor, or not well drained, this way the tree will survive quite wet conditions. Green sapotes can be grafted on mamey sapote rootstock; it can handle wet conditions much better. My experience has shown me that the tree may survive wet periods more successfully, but will drop its fruit in very wet weather. After planting, put a few rocks or concrete slabs on the north side of the newly planted trees, cover the ground and rocks with black plastic, and the tree will grow even in the winter as the ground temperature will be up to 5 deg. C warmer. Green sapote trees will not take more than the lightest of frosts.

I also graft green sapote trees on green sapote seedlings, or marcot them. The grafted and air-layered trees bear fruit in 3-5 years; quicker than trees grown from seed, which bear in 5-7 years. The casualty rate is higher in marcotted trees, this is easy to understand, given their natural habitat in Central America.

They flower in late spring or early summer. The fruit takes 12 months to ripen. Fruit that ripens in spring is not nearly as sweet as summer fruit. Cold weather or too much at flowering can affect fruit set. As the flowering season is quite extended the trees are mostly heavily laden with fruit.

The fruit weighs 200-500 gr. It is green in appearance, turning yellow when ripe. It is delicious eaten fresh out of hand, blended with milk, or served with ice cream. My experience has shown me it is not as popular as mamey sapotes with my Central American customers, and appeals more to Asian and European tastes. Its flavour is milder than the mamey sapote’s, and somewhat sweeter. Its flesh is lighter orange-red, compared to mamey’s deeper red. This suggests to me that green sapote is more suitable for eating fresh, mamey for cooking. My son Peter, who works in the hotel industry, puts a small amount of vanilla or coffee essence in the smoothies he makes, to enhance the flavour, and says both the mamey and green sapotes are fantastic in milk drinks or with ice cream.

Print this entry

• Also see article titled “Grafting Workshop”
• Custard Apple – take the centre out of your custard apples trees.
• Chester recommends Howe Longans as they have big fruit and the tree is dwarf.
• Grafting Black Sapote you need wood that’s been hardened off – don’t use the soft new growth – October. The variety Bernacher is more upright but you get a lot of seconds and it is also bat prone! Maher is more rounded but is susceptible to splitting. The fruit is on the tree for a year.
• Autumn Bliss and Heritage Raspberry – AB is a late season and Heritage is early but AB has better flavour
• Mango – recommended are late season varieties:  Keitt, Palmer, Brooks and they fruit in that order.

compiled by Sheryl Backhouse
 

Authored by: 

Sourced from: 

STFC newsletter Feb Mar 2008

Print this entry

Synonym(s)

Myrobalanus catappa;   Terminalia badamia;  Terminalia mauritiana; Terminalia moluccana; Terminalia myrobalana

Family:

Combretaceae (combretum)   According to the World Agroforestry Centre, the tree is native to Australia, Cambodia, India, Japan, Laos, Malaysia, Thailand and Vietnam.

Common names:

Indian almond, Sea Almond, Beach Almond, Story Tree, Tropical Almond, Wild Almond

I grew up in Bowen, a small town on the Whitsunday coast. Indian Almonds or Sea Almonds as we called them, grew along the beaches, in the parks and in our yards. I have eaten the raw nuts since I was eight years old and for years thought they were the same nuts found commercially packaged at the supermarket as they look and taste the same. The fruits are almond-shaped and green turning brown to purple when ripe. The fruit surrounding the kernel is (apparently) also edible but I haven’t tried it, nor would I like to. About 18 years ago I found myself in Kuranda (north Queensland) without access to food. My friend (from Adelaide) and I had caught the train so were without transport. It was a public holiday and the shops were closed. We thought we were destined for starvation until we noticed an Indian Almond tree towering over the other trees in the rainforest, some distance from the road.  We made our way through the bush and found hundreds of nuts on the ground near the base of the tree. We used a large rock to remove the nuts from the husks (fruit) and we lived on those nuts (and water) for the next two days. The tree has since been a favourite of mine. My mother has (8) 32 year old Indian Almond Trees growing in her yard. When she first moved into the house they were the only plant that survived the beach conditions. They provided mulch which allowed other plants to survive. She now grows ferns, begonias and a magnolia underneath them. She had a sewerage line put in two years ago. The pipe was to pass one trunk no more than 4ft away. The workers told her they did not come across one root. She believes the trees have a very deep tap root and says they are very stable in a cyclone. About 7-8 years ago I asked her for three seedlings. She didn’t think they would survive well at my place in Brisbane as they normally grow in sand and I have shale.

Growing conditions

“The species grows in greatest concentration on sands and loamy sands”. They are “also found on silts, loam, and clays. Soil pH is usually neutral to moderately alkaline and rich in bases. However it will also grow in strongly acid soils. Good drainage is required on clay soils” [www.worldagroforestry.org]. I have seen them growing beside running creeks with their roots in the water. Most of the literature states that it does best in full sun, moist, well drained soil and that it is salt and drought tolerant.  It is not however frost tolerant. The trees biophysical limits are “Altitude: 0-800 m, Mean annual temperature: 15-35 deg. C, Mean annual rainfall: 750-3 000 mm” [www.worldagroforestry.org]. Two of the three trees I planted here in Brisbane survive to this day. They are known to be fast growers (in excess of 1 metre pa) however mine did not appear to grow until six years after being planted out.  Last year they trebled in size. The largest is now about two metres high, a far cry from the 15 – 30 metres they can grow to in ideal conditions. The good news is I have seen specimens that have been kept in pots for years looking beautiful and healthy. Recently my mother visited me and she brought with her eight seedlings and seven seeds. I mentioned to Sheryl that I planned to donate six of seedlings to the club and as a result she asked me to write this article.

Uses:

Food: the kernel is eaten raw (apparently unlike commercial almonds) or roasted and used to “extractable edible oil used for cooking” [www.worldagroforestry.org]. Flavonoids present are “quercetin and kamferol.” [www.tropilab.com/terminalia-cat.html]

Fodder: “The foliage is used as a feed for silkworms and other animal feeds” [www.worldagroforestry.org] including ornamental fish food [www.tropilab.com/terminalia-cat.html]

Timber: “The tree provides a red, good-quality, elastic, cross-grained timber that seasons well and works easily.” “It is strong and pliable and is used for the construction of buildings, boats, bridges,floors, boxes, crates, planks, carts, wheelbarrows, barrels and water troughs” [www.worldagroforestry.org].

Erosion control: “The tree’s vast root system binds together both sands and poor soils” [www.worldagroforestry.org].

Soil improver: “A good provider of mulch for the protection of soil and young crops.” [www.worldagroforestry.org].

Gum or resin: “The trunk is a source of gum” [www.worldagroforestry.org].

Tannin: “Bark, leaves, roots and fruit are all important sources of tannin with the astringent bark containing 9-23% tannin. The outer shell is also rich in tannin.” [www.worldagroforestry.org]. “The tannins contained in the leaf are  s. a. punicalin, punicalagin and tercatein” [www.tropilab.com/terminalia-cat.html].

Dyes: “The trunk is a source of yellow and black dye; it is used in leather preparation and as a base for inks; sometimes the roots and fruits are used for the same purposes” [www.worldagroforestry.org].

Medicinal: I don’t recommend you treat yourself with the tree products for the following disorders or afflictions, rather I feel it is better for you to see your doctor.

a) Liver related diseases: “In Taiwan the fallen leaves of [the] tropical almond are used as a herbal drug in the treatment of liver related diseases” [www.tropilab.com/terminalia-cat.html]. The American Journal of Chinese Medicine [An International Journal of Comparative Medicine East and West], Vol. 25, No. 2 (1997) 153-161 describes experiments carried out in relation to the trees efficacy in treating liver problems in rats. “The results apparently indicated that T. catappa possesses

good antihepatotoxic activity and superoxide radical scavenger activity” [www.tropilab.com/terminalia-cat.html]

The following medicinal uses have been taken from the following sites: [www.worldagroforestry.org] [www.tropilab.com/terminalia-cat.html]

b) Astringent: the leaves and fruit

c) Dysentery: Suriname’s traditional medicine used against dysentery and diarrhoea is a tea from the leaves.

d) Vermifuge: red leaves

e) Leprosy: young leaves, cooked with oil from the kernel

f) Bilious fever, diarrhoea, thrush, and as a remedy for sores and abscesses: bark and roots

g) Headaches: young leaves

h) Colic: young leaves

i) Chemo-prevention of cancer: (this in my mind is always suspect as it may indicate it is cytotoxic. Cancer cells and hair follicle cells etc can be more readily killed by poisons because being fast growing they have high metabolism and therefore take in more toxin than normal cells).

j) Anticlastogenic effect: (i.e. reduces chromosome breakage)

Description:

Some sources describe the tree as “pagoda-like” in that it has tiers of several horizontal branches. The bark is grey-brown. The trunk can be up to 1.5 m in diameter. The trees I have seen in rainforests are often buttressed at the base however those I’ve seen growing on the beaches don’t seem to be. I could be wrong about this though. The leaves are obovate, approximately 30 cm long and turn hot pink- red to orange and yellow before falling. The leaves can fall off a number of times in a year. I’ve noticed mine defoliate during dry spells. Regeneration occurs after being watered. The male and female flowers are inconspicuous, found on the same tree and are greenish white in colour.

Propagation Methods

“The ratio of male to hermaphroditic (female) florets is 16:1.” “Various insects (Coleoptera, Diptera, Hemiptera, Hymenoptera and Lepidoptera) pollinate the flowers” [www.worldagroforestry.org]. “Pollination is not [however] required” [www.tropilab.com/terminalia-cat.html]. The fruit are eaten and the seeds distributed by fruit bats and birds. The seeds float and can be carried considerable distances on the oceans and still remain viable” [www.worldagroforestry.org]. “Seeds for planting are generally gathered beneath mature trees. A suggested pre-treatment is soaking seed in cold water for 24 hours. Germination of the seeds is epigeous. About 70% of ripe seed germinate in about 20 days.”

“Seeds should be set 25 x 25 cm apart in nursery beds. Transplanting to the field is done during the next rainy season.” [www.worldagroforestry.org].

Pests and diseases

Terminalia catappa is said to be susceptible to defoliating insects, especially when young. Grasshoppers and beetles are apparently especially troublesome in Malaysia. Thrips and the West Indian termite Cryptotermes brevis are known problems and the thermophilic fungus Paecilomyces varioti is said to cause die-back of T. catappa seedlings. [www.worldagroforestry.org/Sites/TreeDBS/Botanic] My Terminalias have not had any of the above mentioned problems. Recently, when my other plants were being eaten to bits, my Terminalias remained untouched.

Tree management

Before planting, fertilizer should be applied to poor soils. Although the seedlings develop slowly at first, growth soon accelerates. Weeding is necessary for a few months after planting, but there is soon sufficient cover to shade out competition. It will coppice as a seedling or sapling, but the species is not a strong sprouter. The species is known to form natural root grafts and has natural pruning characteristics. [www.worldagroforestry.org/Sites/TreeDBS/Botanic]

Related readings

Available on request as there are too many to mention or refer to the www.

“Bush Tucker Field Guide” by Les Hidden

Print this entry

 On our property on the upper slopes (300m ASL) of Mt Tamborine, we are blessed with great views, minimum temperatures of only plus 8 (no frost) and a northerly aspect on sloping land that traps a lot of heat and sun. The soils are rich, black and volcanic in nature with a major presence of highly weathered basalt, overlaid by some clay and alluvial soil. Drainage is good once roots get below the thin clay layer. While this all sounds perfect, rainfall has not been perfect by any stretch of the imagination and this has been exacerbated by the northerly exposure with strong winds. Keeping soil wet is a major challenge, especially for newly planted trees. We have planted over 500 trees over the last 8 months, and even with a bore and plenty of water, we still ran into problems. The main issue is water repellancy of the soil once it has dried out. All the books I have read talk about the wonders of compost, sheet mulching with paper to suppress weeds, the joys of deep layers of mulch and many other topics related to the soil nutrition and pH. I am yet to see an article on soil that has dried out and the resulting water repellence problem. So here is my experience and my solution as applies to planting new trees in the sub tropics.

The soil it would seem gets much hotter and much drier than the average garden in Melbourne and Sydney. As a result, some of the practices suitable for conditions down south appear less suitable here in SEQ. The rainfall in SEQ tends to be more concentrated in the summer months with a considerable period of little soaking rain during the dry. This situation was worsened this year (2001/2002) with very little summer rain to date. As a result soils have dried out and irrigation does not alleviate the problem.

When we planted most of our trees, we planted the trees into the best commercially available “organic soil” into a shallow hole. The soil had poultry manure applied and was then covered with wet layers of paper to suppress the weeds with an area around the trunk of the tree to allow water to penetrate. The whole area was covered by a thick layer of forest mulch to depth of 20 cm at least. Liberal quantities of water were applied before the paper was laid and after the mulch layer. We watered religiously for the first 4 weeks and then a sprinkler irrigation system once a fortnight. It was at this time that we notices trees were becoming stressed. The problem became obvious after a simple examination of the root area of the trees. The problems with the system we used are listed below:

• The ‘organic soil’ used did not hold water very well because the organic content was too low;
• The soil applied to the roots was in many cases already water repellent and all the water we applied was shed and thus did not solve the problem;
• The paper had dried out and become an impenetrable water repellent barrier, so all water applied over the mulch was shed. The paper didn’t break down, although in direct contact with the manure, because it was not wet;
• In many cases, the trees were planted above the level of the surrounding ground for extra drainage and this did not allow the water to pool so that the soil, paper and mulch could not soak up the water;
• The sprinkler irrigation system allowed water to penetrate into the soil around the plant, but the “organic soil” did not wick it up because it was water repellent.

 We have now changed our system of planting to overcome the problems listed above:

• The soil used for planting (all soil really) should be kept moist and under a tarpaulin until used;
• The organic content of commercially available soils needs to be increased with compost or other organic matter. We buy soils by the truck load, specify that enriched compost be added and mixed in before delivery;
• Water crystals are always added to the soil at planting time. We apply a wetting agent to the soil, in addition to the water crystals during planting and no paper is used over the planting hole;
• We hand water for 8 weeks after planting and never, never let the soil dry out during this period;
• We plant in spring and summer now so that we catch the increased rainfall and also allows more cold sensitive plants to become established before the colder months.

If you are in the unfortunate position of having water repellent soils around your plants the only solution is to physically agitate the soil with a jet of water. Simply sprinkling the surface of the soil will NOT work no matter how long you water. The water jet method works well, but you do need to be careful that you do not damage the roots of the plant. Applying a wetting agent before you break the water repellency does not work either. Wetting agents can be applied after you have solved the problem, then the wetting agent helps to keep the problem under control.       Happy Gardening

Print this entry

Joe says you can induce seedless fruit on pummelo by spraying with GA3 (Gibberellic Acid) when the plant is at 50% bloom. He wrote to not spray before bloom because that would prevent blooming.  Before the bloom opens, there are reproductive buds, or unopened flower buds that are pyramidal shaped and about 1 to 2 mm diameter. If you spray GA3 at that stage, they will revert back into vegetative buds, thus you prevent blooming. 

Technically, you minimize blooming when you spray GA3. Because of non-uniformity of statistical distribution of stages of bloom, a few of the flower buds would be at the point of no-return and wouldn’t revert back to vegetative stage, but there is a stage of the unopened flower bud that can revert back into vegetative buds when sprayed with GA3. During 50% bloom, I meant that approximately 50% of the flowers have opened and are receptive for pollination.

We know that this is a population of distribution of stages of flowers, numbering in the hundred thousands or millions within a canopy, and for sure they don’t have the same phenostage, and you would have various stages from unopened flower buds to petal fall, but approximately 50% of them are open and are receptive for pollination. When the flowers have opened and they are sprayed with GA3, the flower is tricked into reacting that it has been pollinated and so the fruit would set without forming any seeds, and thus we have seedless fruit.

This has been observed with watermelons, and other fruits.  Again, it is not 100% seedlessness because of the population distribution of the stages of flower, and some of them have already been pollinated before the application of GA3 but majority of the fruits would be seedless, to those that were receptive but have not been pollinated and received a whiff of GA3, and then you would have tremendous fruit sets that are seedless. 

Because you would have tremendous fruit set, you may need to spend extra labour to thin out the crop but that depends on your flower density, and so you may have to apply GA3 either at 25% open blooms or even at 10% but this depends on flower density. If you have few flowers, the 50% bloom would be the best time, but if you have a tremendous amount of flowers, you may need to spray during the 10% bloom. Some of the blooms would revert back, depending on the stage of the flower, but those that are open and are receptive for pollination would have fruit set that are seedless when sprayed with GA3. You can search for the references about GA3 application in citruses on how to control the alternate year bearing in Clementines.