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Last year I grew jicama in my vegetable garden and I can recommend it as a vigorous, easy to grow and unusual edible tuber. Jicama is a climbing vine producing large, sweet, heart-shaped crispy tubers and is used as a salad vegetable or as a crunchy addition to fruit salads. It can also be cooked and used like water chestnuts. The tuber is very crisp when peeled and sliced. It can be eaten raw, garnished with chilli pepper and lemon juice, salted, used a vegetable sticks with dips, or stir-fried.

Jicama originated in Mexico and is also known as Mexican yam bean, Mexican potato or Mexican water chestnut. It is a high-protein, low fat dietary staple in many areas. Sometimes another vegetable, the Yacon, is also called Jicama although it is a completely different plant. This is because the word “Jicama” means “edible root” in Spanish (see my article on Yacon in the last issue).

Please note that, unlike other beans, the seeds, pods, leaves and flowers of jicama are poisonous.

Mature pods and seeds contain ROTENONE, a potent poison. It is only the tuber that can be eaten.

Jicama is a member of the bean family, (the Leguminosae), so like other legumes, it fixes nitrogen and produces pods and seeds. It is easily grown from seed. If it flowers, these should be removed, as flowering will reduce the root size. Dig the tubers when they are small – about 10 –15 cm, as larger roots may become  woody. Usually the foliage will have died down by this time. The roots may be safely stored in the refrigerator.

The only problem I had growing jicama was slugs having a nibble at the tubers. This can be controlled with snail bait (organic snail bait is available).

Easy Jicama Salad

1 small jicama tuber, 1 capsicum, 1 zucchini and 1 carrot

Peel and slice the above into thin julienne strips. Dress with a mixture of 4 tbspns olive oil, 2 tbspns lime juice, salt and pepper.

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Dr. Greg Partida, who has been teaching at Cal Poly for the last 30 years in the area of Ag Biology and Fruit Industries, gave the lecture on avocados. He has a B.A. from Cal Poly in Agriculture Biology, an M.S. and a Ph.D. in Integrated Pest Management at U.C. Riverside. He was Farm Manager of the University orchards for 23 years and has consulted in the cultural practices of avocado throughout the California production area and in the Dominican Republic.

In California the avocado industry is undergoing radical changes, mostly due to competition from other countries, the increasing costs of production and worker’s compensation insurance. The avocado tree of the future will be no taller than an average man can reach in order to dispense with the use of ladders in the orchard.
It is Dr. Partida’s opinion that any grower with trees that cannot be pruned, sprayed and harvested by a man standing firmly on the ground will be out of business in five years.

His most important point was that most avocados are under-watered. This is particularly important during the flowering period. He is a great believer in mulching and states that you should leave all prunings under the tree to release their nutrients back into the soil. Avocados love cow manure and you should heap aged manure in a donut shape around the tree just as you would spread fertilizer. Do not leave it up against the trunk but pile it up in a ring to out past the drip line so the feeder roots of the tree will come up through the mulch. This goes back to lots of water!!! With roots at the surface the tree needs adequate moisture without sitting in water.

The leaves on a healthy avocado should be 12 to 15 inches long and 8 inches wide. If your tree is under par, Dr. Partida recommends a combination of humic acid and P205 fertilizer used as a soil-drench twice a month for sick trees. The humic acid should be mixed at a rate of 1 oz: 1 gal. humic acid is one of the most biochemically active elements in humus and he swears by it to stimulate wood growth. It is a liquid product derived from decayed organic matter with a capacity to collect plant food elements and release them as the plant requires.

The last recommendation he made that was unusual was to plant three to four varieties of avocado in the same hole to increase pollination, yield and lengthen harvest times. This procedure was backed up by another speaker in his lecture on Backyard Orchard Culture.

“Festival Of Fruit” Pomona, California, June 18 To 21, 2004
www.mrfc.org/articles/notes/

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I asked the rarefruit yahoo group what control methods they used on their trees to protect against frost and Roger Meyer from California and Erica from Florida said to cover the tree with old sheets right to the ground. You can pin the sheets together with clothes pins. You must use fabric. Shadecloth does not work. Then you need a heat source under the tree and various methods were given by other members eg. a lighted candle, outdoor Christmas lights, or you can take one of those outdoor extension cords, which also has a hanging hook and light socket at the end and hang that under the sheets on a tree branch. This will keep the temperature a few degrees warmer than the outside. Another of our members in Sydney, Jason Rukowski, has also been affected by frost so he has also purchased Marix fabric which will be used next year for cold protection.   Several of our members have also used the product Envy without success. I looked up their website and it says: Envy is a frost protectorent and anti transpirant which can substantially reduce moisture losses by up to 50%, eliminate sun & windburn damage as well as increase frost tolerance by an additional 4 Degrees. 

From a rarefruiter:  “It was incredible to see the results of our frost protection and the damage that an extra degree can do to plants. Our sprinklers come on when the air temperature reaches 0 degrees, this was at 11.30 pm last night so by sunrise there was a thick coating of ice over everything. The ice prevents the cells inside the plant from freezing and therefore prevents damage by the frost. The sprinklers stay on all night so by the morning there is a thick layer of ice covering the plants. As it melts the plants do not suffer from internal damage and as you can see these young seedlings do not look as though they have been through a -4 degrees frost. What happens is when you sprinkle water on the plant ice forms but when new water goes onto the plants the original ice that has formed around the plants releases heat of up to 10 degrees which protects the plant. The application of water has two beneficial effects regarding frost protection. The drier the air becomes then more heat is lost into the atmosphere, so humidifying the air reduces the amount of heat radiated away and the severity of the frost. The constant application of water to plants maintains the surface temperature around zero-ish degrees which is generally more tolerable and less damaging than if it continued to drop to several degrees below zero.”

Authored by: 

Compiled by Sheryl from the web

Sourced from: 

Sub-Tropical Fruit Club of Qld. Inc Newsletter October – November 2007

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You don’t need to wait for 10 years to know if you have Langsat (Lansones), Duku or Longkong if you planted a Lansium species by seed. Mature Duku trees don’t have the bitter taste in the leaves so you need to compare the leaves of Duku and Langsat to know the difference. Sometimes even fruit experts have a hard time identifying Lansium species especially when they are looking for superior species or selecting a superior species of Langsat. In my experience, Longkong and Langsat tend to grow vertically, while Duku grows horizontally and tends to have a wide canopy if not pruned properly. If you really want to know what Lansium species you have, try tasting their leaves.  Langsat has a bitter taste on the leaves that’s why also when you accidentally bite on the seeds you get the bitter taste.  Sometimes we mistaken Langsat and Longkong for the same because of leaf similarities but this how we differentiate between them. On the other hand, Longkong has no bitter taste in the leaves, try eating the undeveloped seeds and small seeds, you could eat Longkong even the seeds that’s why people say its seedless because even the seeds could be eaten because of no bitter tastes but often Longkong fruit have no seeds at all and only have undeveloped seeds in it so chances of getting a big seeded Longkong is like 1:15 ratio.  I already have done it, and it’s funny because I am not accustomed to eating a Lansium with seeds in it because we always eat Lansones and spit the seeds.

Also there is a way to avoid the gummy latex in Langsats. When you squeeze them properly, the tendency is that you’re going to have less gummy latex in your hands but if you’re an erratic eater of Langsat then you will need to wash your hands after eating to remove the gummy latex –  alcohol should do the trick! 

Warning:  Never eat a kilo or 2 of Lansones or any of the Lansium species without eating anything.  It is the custom here to eat Lansones after meals for dessert purposes but for a snack, eat 2-5 fruits only or regret it. It’s too acidic to eat Lansones on an empty stomach. 

To summarize: Duku has shallow, thin, crenate, smooth leaves. No bitter taste in leaves of mature trees. Horizontal canopy. Langsat (Lansones) has shallow, thick, acute, hairy leaves. Bitter taste on leaves & seed. Tree grows vertically.

Longkong has deep, thick, crenate and smooth leaves.  Leaves not bitter.  Tree grows vertically.

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It has been known by several common names including Chilean Guava, murta, murtilla and Tas Myrtus Berry. In New Zealand it is being erroneously sold and marketed as the ‘NZ Cranberry’. It has a taste of a combination of strawberry, pineapple and apple. The plant is a native to Chile and is a small evergreen shrub with small leathery leaves. It grows to a size of about 1.7m high and 1.5m wide and tolerates a wide range of soil conditions. Once established the plants do not mind drought conditions but watering during establishment is a good idea. A good thick mulch/compost is also appreciated. Some texts list the plant as being frost sensitive, others do not. Slow growing evergreen bush forming a compact shrub of approximately 1.5m. Self-Fertile. This attractive fruiting plant has small dark green leaves with new growth tinged with red. Grow it as a low growing hedge, in a container or as a garden specimen. In summer this plant smothers itself with fluffy white flowers. Flower in summer and fruit is ripe February to March. This attractive small fruit is red in colour. Allow fruit to become lighter in colour before harvesting to ensure the best taste. The taste can only be compared to a tiny sherbet bomb – sweet and tart. Best eaten on its own to really appreciate its aromatic flavour. Great also as a jam with punch, or a sauce topping for ice cream. The Ugni is frost hardy and will grow in any soil providing there is moisture. This plant, unlike most other fruiting plants, grows and fruits well in partial shade. Prune after fruiting to maintain shape.

Propagation   Seedling tubes with plants 25cm tall are the best to plant. 1.5m (in row spacing), 2–3m between rows to allow access.

Yields  1kg of fruit per plant in Year 3. A 1kg increase per plant each year from Year 3 onwards.

Sheryl:  I recently attended the Elleslie International Flower Show in Christchurch and tasted these small fruit. Well worth putting a couple in.   Good article in Louis Glowinski’s book The Complete Book of Fruit Growing in Australia

Authored by: 

STFC newsletter Apr May 2010

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 Methods of fruit fly control have not changed markedly over the last decade. The following are the methods that people can consider:

Dick Drew:  1. Protein Bait Spray: Pinnacle Yeast Autolysate applied as a spot spray to fruit trees, usually gives adequate control when applied over large areas (i.e. in small urban backyards, it is usually not very effective unless a number of households implement the strategy collectively). For best results, the protein is applied in approximately 50ml spots per tree when the fruit on the trees are at the mature green to ripe stage. That is because the fruit trees bearing ripening fruit attract the flies into the area, which can then be targeted with the baits.

2. Netting: Using 50% shadecloth or other netting with a similar gauze size will exclude fruit flies. This works well in the small urban environment (backyard, lot, etc.). It has the advantage of excluding birds, possums, and other pests that feed on fruit, as well as giving protection against fruit flies. For fruit trees, it is best to prune them to a manageable height, and then cover the entire tree with the netting. Trees that cannot be pruned can have branches covered in netting sleeves.

Sheryl  –  I will be making up some sleeves using various types of netting so you can slip them over whole branches as some of the bags that were used by members were not successful.

Oscar

• Focus on fruits that fruit flies don’t like.
• Pick fruits while still hard, before the fruit flies sting them eg pick pawpaw just as they turn yellow.
• Bag all fruits.
• Eco Naturalure attract male and female flies.

Try making a fruit fly trap. All you need to buy is a small bottle of methyl eugenol which is a pheronome attractant. Use an empty one gallon milk plastic bottle. Dip an ear cotton swab in the methyl eugenol and attach it to the lid, so that the cotton dipped swab is on the inside of the bottle. Punch a few pea sized holes on the top of each side of the bottle. Place an inch of soapy water, dishwashing soap, on the bottom of the container. The flies will enter, fly around and drown in the soapy solution. Hang these bottles away from your mango trees. Inspect weekly and empty as necessary. I have read also of people using sticky tape and putting a few drops of the methyl eugenol on the sticky tape. This might be easier in areas with very few flies.

Ken   Bags work great especially in combination with the methyl eugenol lures.

Pests and Diseases Image Library (PaDIL) has great photos of pests or diseases. It is a Commonwealth Government initiative, developed and built by Museum Victoria’s Online Publishing Team, with support provided by DAFF (Department of Agriculture, Fisheries and Forestry) and PHA (Plant Health Australia), a non-profit public company. Project partners also include Museum Victoria, the Western Australian Department of Agriculture and the Queensland University of Technology. Additional image providers include: Dr Laurence Mound (ANIC, CSIRO); Dr Roger Shivas (Queensland Department of Primary Industries); and Dr Mallik Malipatil (Agriculture Victoria, Department of Primary Industries).      http://www.padil.gov.au/

Using Pesticides

Find out the latest news on labelling, such as recent changes by visiting the Australian Pesticides and Veterinary Medicines Authority (APVMA) website on  http://www.apvma.gov.au/  If you don’t have the right equipment, only choose licensed spray contractors to carry out your spraying needs. The ´Search for a Sprayer´ section of the DPI&F website is a good resource to check this.

Errol  & Regina’s recipe:  I’ve had good success with Wild May in controlling fruit fly. We tried the standard soft drink bottle method where you put the WM in the bottom of one bottle and have access for the FF through 2 cut-off tops of soft drink bottles one on each side of the main bottle however because of the cost of the wild may, Errol decided to change over to a new system he saw in the Mackay RFC newsletter.  We got a plastic peanut butter bottle with a wide top then put a bit of wire through the lid and hung a bit of polystyrene soaked in WM. This didn’t seem to work so he modified the system and got a small vanilla bottle and hung that inside the plastic peanut butter bottle and put a piece of foam rubber in the neck of the vanilla bottle 50ml cut the top off the plastic vanilla bottle and put a couple of pieces of wire in the top and hook it through the lid of the peanut butter bottle and put the WM in that then put some water in the bottom of the container so the WM attracts the bugs but the WM doesn’t get full of insects so you don’t have to keep straining it. Half an inch of water in the bottom of the peanut butter.

Annette McFarlane reports: Yates has discontinued production of several chemicals based on the active ingredient, Malathion which also goes under the name of Maldison. Also to go will be products based on Carbaryl and Dimethoate eg Rogor.  Less toxic or naturally derived alternatives such as Confidor, Dipel, Success, Pyrethrum and PestOil are suggested as substitutes.

Fruit Piercing Moths:  When near ripe fruit develops soft spots that cause premature ripening, fruit fly is often to blame. Breaking open the fruit will reveal larvae which help to confirm the diagnosis. When no larvae are present, suspect attack from the fruit piercing moth. As moths are active at night, few gardeners ever encounter them. Fruit sucking moths are large with a wingspan of up to 6cm. The wings are usually dark brown with distinctive orange markings. The moths pierce the skin of pawpaw, tomatoes, citrus, persimmons, bananas and other fruit then suck out the liquid contents. A black spot remains at the point of entry with flesh around this either becoming soft and pulpy or dry and pithy, depending on the fruit attacked. Spraying is not an option. Either pick the fruit before it is ripe, cover with paper bags. An outdoor light that attracts insects is an option but remember that it will attract a lot of other insects including beneficial ones.

Fruit Fly Bait for Organic Growers

Organic growers may finally have an effective control against fruit fly. Naturalure^™ Fruit Fly Control Bait is a BFA registered organic fruit fly control product for male and female Queensland fruit fly and Med Fly and has recently received APVMA registration. Naturalure^™ is a specially formulated protein bait spray for attracting and killing both male and female fruit fly. The active chemical in the product is based on the same active found in the BFA registered organic caterpillar and thrip spray Entrust Naturalyte^™ Insecticide called Spinosad – a naturally occurring toxin produced by a soil bacterium.

Naturalure^™ is now used as the benchmark bait treatment for both male and female fruit fly around the world. The main advantage over other bait sprays is that it attracts females as well as males, so it is a complete fruit fly control bait. Because of the highly attractive nature of the bait, the application rates are half that of other bait sprays. The other advantage it has over conventional bait sprays is a low impact on beneficial insects. Applications are targeted at the foliage in the upper parts of the tree and contact should be avoided with fruit as there is a chance of burning. Mangoes are particularly sensitive to the bait spray. TM- Naturalure is a registered trademark of Dow Agrosciences and is available from BFA registered company Organic Crop Protectants.     www.ocp.com.au  Best to spot spray foliage – not fruit as some can blemish

Over the last few years I lost most of my guava crop to fruit fly so last year  I tried Wild May in combination with Eco natural lure and it works.  The first year I still lost a small amount to fly but I kept the traps out all year.  This really wipes out the males and the Eco natural lure takes care of whatever is left. I had a somewhat controlled experiment with my trees at work – they were totally infested but at home I had a good untouched crop.  I was usually getting four to five flies per trap at home per week but now that’s down to about two. At work I had, no word of a lie, in the first week, 50 flies per trap.  I place the traps about 10-20 metres apart not the 50 metres as advised after that the numbers started to drop to the point whereby now I only catch 4 per week.    Jason Rukowski – Sydney

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In Australia, the Autumn months are March, April and May.

Now is the time to plant out new fruit trees. If you live in a frosty area then spring would be preferable. To reduce frost damage in winter, don’t apply high nitrogen fertilisers in autumn. Fertilize with potassium rich “flower and fruit” fertilisers. Don’t overfertilize. If you do, then the new growth is soft and can bring in the pests.You can also foliar fertilise with a seaweed spray as this helps thicken cell walls to better resist frost. and put out a handful of Cal/Mag per sq.mtr. on your trees. Watch for Fruit Piercing Moth – net your trees / use fruit fly traps or sprays. If ants are a problem in your trees, then apply a sticky band around trunk of trees to keep ants at bay thus reducing scale. Tie a piece of cotton around first, don’t apply the sticky substance direct onto the tree

If some of your trees are not fruiting, give them some Sulphate of Potash with a bit of Urea. Peter Young from Birdwood Nursery says that if the flowers on your fruit trees are aborting, spray the following recipe on all flowers of your fruit trees – no need to use it on citrus. He emphasised that it must be sprayed on just when the flower starts to emerge although in Israel they put it on Lychee when the flower is 5-6mm.  Mix 1gm Borax in warm/hot water with ½ gm Urea and 1 litre of water or if you prefer to use Solubor instead of Borax, you only use half a gram as it is twice the strength.

To decrease damage from frost, remove mulch from around sensitive plants. This has the effect of heating the ground temperature, it is warmed in the day by the sun and that warmth is released at night. It will be important to replace this mulch in the spring when the risk of frost has passed and the ground temperatures have risen. You could also apply weed mat which warms the ground.

Authored by: 

Sourced from: 

STFC Newsletter April – May

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When we think of berries, we generally think of temperate zone plants like strawberries, blueberries, raspberries and blackberries. The term berry is defined simply as a fleshy fruit with one or more seeds. By tradition, the term is applied mostly to small fruits. Although the Year of the Berry has concluded, I would like to discuss here a group of Central and South American fruits that could be considered the South and Central American equivalents of our temperate zone berries, the genus Eugenia. The Eugenias belong to the large plant family Myrtaceae or myrtles. The myrtle family includes many fruiting plants, the best known of which is the ubiquitous tropical guava, Psidium guajava. Other genera within the Myrtaceae grown for their fruits include Feijoa, Myciaria, Campomanesia, and Syzygium. The genus Eugenia is exceedingly large. A search of the International Plant Names Index at the Royal Botanic Gardens, Kew gives 235 pages of entries at about 20 names per page. Even allowing for duplications and synonymy, there are more species in this single genus than the entire flora of most temperate zone regions. Many of these, if not most, bear edible berries. At one time, the genus name Eugenia was applied to species in both hemispheres but recently, the Old World species have been separated into the genus Syzygium. I will limit myself here to a discussion of eleven New World species already in cultivation. There are undoubtedly many species not in cultivation worthy of domestication. I’ll leave that to some future intrepid plant explorer. The most common Eugenia found in cultivation is Eugenia uniflora or Surinam Cherry. Other names for this plant are cereza de cayena and Pitanga. Surinam cherry, despite its common name, is originally from Minas Gerais and Rio Grande do Sul in southern Brazil. In its native habitat, it is a tree up to 10 metres in height. In those parts of the United States where it can be grown, it is more commonly seen as a bush, often used for hedges. It is a subtropical plant and when established will tolerate down to -5° C. The fruit are small and prominently ribbed.  When ripe, the colour varies from orange-red to dark red. The darker fruits are said to have better flavour. The flavour is sweet and somewhat resinous. In Brazil, it is used to flavour candies, carbonated drinks and frozen desserts. Surinam cherry is easily grown from seed and plants begin bearing at an early age. However, many sources suggest that for better fruit, it is preferable to purchase grafted plants of known quality. It is tolerant of a range of soil types but performs best in neutral to slightly acid soils with moderate humidity and watering.

Probably the next most common Eugenia in the U.S. is Eugenia aggregata or Cherry of the Rio Grande. The name refers to Rio Grande do Sul in Brazil and this plant, like the one before, is a subtropical. It is a large shrub to 5 metres and when established, also hardy to -5° C. Opinions on the quality of the fruit vary but it is a popular fruit in Brazil for making jelly, jam or juice. The fruit is sweet and dark red when ripe. This plant prefers slightly acid soils and even moisture, being easily damaged if allowed to dry out. Plants are said to begin fruiting at about 5 years of age. It is an attractive plant, whether fruiting or not.

Eugenia brasiliense or grumichama is a tree to 20 metres native to the Atlantic coast of Brazil. It comes in three varieties according to fruit colour, yellow, red and dark vermillion. Fruit are sweet and largely consumed fresh, being produced in great abundance from about 4-5 years of age. Fruit drop can be a problem. The tree is very ornamental and established plants will tolerate temperatures down to about -3° C. It has one of the shortest maturation periods for fruit known, going from flower to ripe fruit in 30 days.

Eugenia luschnathiana (syn. E. dombeyi) or Pitomba is also native to Brazil and when fully grown, a tree 8 metres in height. The fruit are somewhat larger than the preceding three species, orange at maturity and about 2-3.5 cm in diametre. It may be eaten out of hand but in Brazil, is more often made into preserves or juices. This plant does not tolerate freezing temperatures but has the redeeming characteristic of fruiting when still small, suggesting utility as a container plant in warm temperate climates. Seeds are slow to germinate and appreciate high humidity at germination. Mature plants will accept lower humidities but fruiting may be impaired if humidities are too low.

The species that follow are not well known outside of their native regions but are of sufficient quality to be worthy of wider cultivation. Most are native to Brazil with a couple of exceptions.

Eugenia stipitata is mentioned in Julia Morton’s Fruits of Warm Climates as a promising fruit. It is native to the Amazonian region of Brazil and Peru and is highly regarded by local inhabitants. It is cultivated in

Peru to a limited extent with the fruit processed to pulp and exported. There are two subspecies. Eugenia stipitata stipitata is a large tree, abundant in the western Amazon basin, heavily utilized by local residents. Eugenia stipitata soraria is a large shrub or small tree and is the variety cultivated for fruit because of its more manageable size. One major reason for the interest in this plant as a fruit crop is that the fruit are much larger than most Eugenias. Fruit on cultivated plants have been known to weigh up to a pound. Because of its tropical origins, this plant would most likely be suitable for cultivation only in South Florida or Hawaii.

Eugenia pyriformis, known in Brazil as uvaia, is from São Paulo and Rio Grande do Sul. Uvaia is a tree to about 10 metres. As the species name suggests, the fruit is somewhat pear shaped, turning yellow to orange when ripe. Fruit are 3-4 cm. in diametre. It is frequently cultivated in Brazil in home orchards, with the fruit being utilized for sweets.

Eugenia leitonii, is known as araça-piranga or goiabão and is another Brazilian species. It is a tree to 8-14 metres and is found from the south of Bahia state to Paraná in the south. It is apparently a slow grower and appreciates humidity. The fruit is yellow when ripe and sweet but only a thin layer of flesh covers the single large seed.

Eugenia tomentosa or cabeludo is a shrub from the Amazonian region. It grows to 2-3 metres in height. The fruit are 3 cm. in diametre and yellow when ripe. It is utilized by local inhabitants and has seen some cultivation. As its origins imply, it would need humidity and warmth to prosper, making it another species best suited for southern Florida and Hawaii.

Eugenia candolleana is another species with edible fruit from Brazil that I have in cultivation. As the image shows, the fruit is purple when ripe and very edible (personal communication Luis Bacher). Beyond this, I have no information on habit, origin or cultivation.

Three other species I have growing and for which I have little information are Eugenia reinwardtii or Cedar Bay Cherry, Eugenia subterminalis or mulchi and Eugenia victoriana or guayabilla. Eugenia reinwardtii is an exception to the general rule that Eugenias are western hemisphere plants. This plant is found growing in Australia and Southeast Asia, often, as the common name implies, near the seashore. The remaining two species are from Ecuador, a center for tropical diversity in South America. Both bear edible fruit. My plants are still seedlings. Eugenia subterminalis seems to be a vigorous plant, tolerating my hot dry conditions with no signs of ill effects. Eugenia victoriana, on the other hand, has been set back by our winter and is struggling with the low humidity here.

Most Eugenias are from tropical and subtropical areas. They appreciate warmth, humidity and even soil moisture, neutral to acid soils are preferable but they seem to handle some alkalinity here in Tucson. Propagation for most species is from seeds. Some seeds germinate rapidly but others may take many months to appear. Seedlings, especially of the tropical species, are susceptible to thrips at emergence and tip blight from low humidity. While I found no reference to production of plants from cuttings, at least one reference felt it likely to be possible. Grafting of superior clones, at least in the instance of Surinam Cherry, is successfully employed.  I grow my plants in containers because in the ground here in Tucson they are susceptible to grubs, Texas root rot and chlorosis. This might not be a problem in other areas. The above ground parts are not bothered by insects. In humid climates, they will want full sun but in the desert, they do better with filtered light. Regular feeding with a balanced fertilizer is also appreciated. Growth rate is moderate and most species under good conditions can be expected to begin flowering by 5 years of age. If your fruit interest is in variety and like me, you cannot grow temperate zone berries due to climate, consider adding Eugenias to your home orchard. Plants and seeds are available from numerous sources and they are attractive as well as useful. I would be interested in hearing from others who have experience growing these interesting plants. Finally, I would especially like to thank my friend Luis Bacher in Limeira, São Paulo, Brazil for allowing me to use his photos and for the seeds he has sent me over the years of these and many other beautiful plants.  Ref:  1. Fruit of Warm Climates – Julia Morton. 1987   2. Frutas no Brasil – Silvestre Silva and Helena Tassara. 19963. Árvores Brasileiras – Manual de Identificação e Cultivo de Plantas Arbóreas Nativas do Brasil – Harri Lorenzi. 1992  and 4. All About Citrus & Subtropical Fruits – Ortho Books. 1985 

The author of this article Chris Marshall MD resides in Tucson, Arizona and grows arid-zone plants, including cacti & succulents.

Sheryl:  I met Chris when I was their guest speaker last year. His article included photos of the plants mentioned but space does not allow us to include them so check for them on the web or have a look at the Fruit Gardener Magazine in our library. He is looking for Brachychiton seed; particularly chillagoensis and paradoxum. Hybrids, as well as species would also be welcome. He’s willing to pay & has already collected:

acerifolius, acuminate, australis, bidwillii, discolour, diversifolia/populneus, gregorii, megaphyllus, rupestris.

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After attending a weekend of talks at Fairhill Nursery last year where I caught up with Nan & Hugh Nicholson (they wrote that excellent series of rainforest books) Nan mentioned that in certain species of Macadamia the kernels contained traces of cyanogenic glycosides.  This was the first I had heard about toxicity in Macadamias and thought I would go looking for other sources of information to do an article for our newsletter. Our previous Guest Speakers Merv & Elwyn Hegarty also knew about it and sent me some detail on the subject. The final piece of information came while I was attending a lecture by Dr. Ross McKenzie on “Cyanide, Strychnine Bush and other poisonous hazards in the Queensland flora”. He sent me an article that appeared in Australian Vet Practitioner 30(1) March 2000 and to summarize:

Plants in the genus Macadamia (family Proteacae) are endemic to eastern Australia (seven species) and Sulawesi in Indonesia (one specie) (Gross 1995) Macadamia tetraphylla, M integrifolia and hybrids of these species – variously known as the Macadamia Nut tree, Qld. Nut tree or Bopple Nut tree are cultivated in Australia, Hawaii and elsewhere for the edible kernels. Some kernels of these species contain traces of cyanogenic glycosides while the kernels of M. ternifolia and M. whelanii contain significant amounts of cyanogenic glycosides, are bitter and not currently used as human food (Aboriginees would remove the toxins before eating them (Gross 1995).

In the clinical study, thirteen adult dogs of both sexes, various ages and at least five different breeds  developed sudden onset of various combinations of either paralysis, pain in the hindquarters, listlessness, limping 6-24 hours after eating several kernels etc. with one Rottweiler being given 2 tablespoons of macadamia butter.  All dogs recovered within 24 hours.

The close association between ingestion of kernels and the onset of the syndrome in dogs and the consistent signs displayed among cases strongly support the hypothesis that toxicity from a chemical or chemicals in the kernels was responsible for the syndrome. Such chemicals may well be part of the plant’s defence system protecting its genetic material from attack by insects or microbes. The only known toxins in Macadamia spp. are cyanogenic glycosides. In one case where roasted kernels were fed, it indicates that heat does not denature the toxin or toxins.

Given the widespread consumption of Macadamia kernels by humans and the lack of reports of subsequent poisoning, this syndrome appears to be a further illustration of the differing reactions of mammalian species to plant toxins. Dogs and humans for example differ significantly in their likelihood of being poisoned by theobromine in chocolate (from Theobroma cacao) and their susceptibility to N-propyl disulphide and thiosulphates in onions (Allium cepa). Dog owners should be warned not to regard their animals as “small humans”. As M. ternifolia is native in the area where I live, I rang our local Veterinary Clinic which has a large country practice (the Vet is an ex-President of the Australian Veterinary Association) and they said they have never come across this syndrome in their practice. I am a little surprised by this as our “Chuck” (actually – Charles Henry Robert Backhouse – the Bull Terrier) who actually belonged to the neighbour but lived at our place during the day could crack an unshelled nut with his teeth – loved them.