Stink bugs – update

stinkbug2 An environmentally-friendly way of getting rid of stink bugs is to use a stick to knock them into a container with some methylated spirits in the bottom of it, so that you don’t have to come in direct contact with these smelly bugs that change colour from green to orange to brown-black as they grow.
However, a reader e-mailed me this week about his problem with lots of stink bugs on his orange tree that is too tall to use this method, and he wanted to know if he could spray the tree with metho, instead.

Spraying the bugs with methylated spirits would only further damage the tree. If you also have a tree affected by bronze orange bugs (stink bugs), these bugs are a sign that a tree is very under-nourished. It is probably extremely water-stressed, as plants can’t absorb nutrients from soil if it is not damp enough for the minerals to become water-soluble. Give the soil around the affected tree a thorough watering, then give it an application of complete organic fertiliser and then water in some organic seaweed tea. You haven’t said which climate area you live in. If you live in an area where water shortages are common, keep the tree pruned to a size where it can remain healthy on the amount of water that you and nature can provide.

Bronze orange bugs or stink bugs and harlequin bugs are sap sucking pests that can do a lot of damage to stressed citrus trees. Spined citrus bugs suck sap from fruit. Before dealing with these bugs, you need to don old clothes, sturdy shoes, gloves and goggles or sunglasses as bronze orange bugs eject a corrosive fluid with a vile smell when they are threatened.
Young bugs tend to cluster under the lower leaves of the trees and are easy to get at, but if trees are too large for knocking them into a tin, spread some large sheets of plastic under the tree, then use a broom stick or long pole to give the foliage a good shake and, when they drop to the ground, either squash them, or gather up the plastic and slide them into a large container with a suitable pest treatment in the bottom.
Organic-registered products such as Natrasoap (not ordinary soaps or detergents) or Eco-oil will kill these pests but they should not be used on heat-stressed or water stressed plants, or in high temperatures. However, either of these products can be used to spray stink bugs when they shelter around the base of the tree on hot days. Harlequin bugs like to shelter in weeds, and they can be sprayed where they are hiding. Get rid of weeds, particularly along fence lines to prevent re-infestation.
However, the best way to avoid these horrible pests is to take good care of your citrus trees.

Derris dust

Following my post on organophosphates and ADHD, one of my blog readers asked for more information about derris dust (rotenone) that has been popular with organic gardeners for pest control as rotenone is an organic pesticide made from the roots of a tropical plant. It also has a long history as a piscicide (fish killer).
Rotenone works by shutting down energy production in cells, which makes it a neurotoxin. Research linked it with Parkinson’s Disease, but this was largely discounted as the rats in the research had rotenone injected directly into their brains, which is not a very fair trial.
In 2007, the USEPA published a Re-registration Eligibility Decision (RED) assessing only the risks of contact from its use as a piscicide (i.e. swimming in or drinking treated water). The RED stated that small children and foetuses were more susceptible to the effects of rotenone.
www.environmentalhealthnews.org/ehs/blog/health-ecosystem-effects-of-rotenone-ignored
According to Environmental Health News, researchers have found that rotenone selectively destroys dopamine-producing cells in petri dishes. (The full document on this research must be purchased).
In 2010, another study was published about research in mice that showed a progression of Parkinson’s-like symptoms after mice were fed low doses of rotenone over a period of time. The research found that concentrations in the central nervous system were below detectable limits, yet still induced Parkinson’s Disease pathology.

Australia’s APVMA has reviewed rotenone and decided that it can still be used as a pesticide. However, both Canada and the United States are phasing out the use of rotenone for everything except its use as a fish poison. In Canada, for example, rotenone could not be sold for livestock, gardening, or domestic pet use after the end of 2008, and existing stocks can’t be used after the end of 2012.

I certainly don’t recommend the use of Derris dust, but gardeners must make their own evaluations of this pesticide.

Organophosphates and ADHD

Earlier this week, ‘Today’ program on Channel 9 aired a segment about new research showing a link between organophosphate pesticides and ADHD. The research involved 1,139 children between 8 and 15 years and found high levels of organophosphate metabolites in urine of children with ADHD. This link is not surprising as organophosphates (and carbamates) are neurotoxins. These pesticides work by affecting the central nervous system, and organophosphates were developed for chemical warfare before being used as pesticides.
Both organophosphate and carbamate pesticides block the action of the enzyme acetyl cholinesterase, which regulates the transmission of nerve messages. Well-established research has shown that chronic exposure to organophosphates induces neurological dysfunction. Children are more susceptible to all toxins, including neurotoxins.
Separate research has linked pesticide exposure with Alzheimer’s disease and Parkinson’s disease. Included in the suspects is the very popular Derris dust, which has also been found to be a neurotoxin.
‘Today’ presenters advised that all fruits and vegetables should be carefully washed before eating. Good advice to be sure, but advice that misses the point that some organophosphate pesticides commonly used on food plants are systemic. Systemic pesticides enter the sap system in plants, are distributed to all parts of the plant, and can’t be washed from our food. As a lot of our food is now imported from countries with differing standards for pesticide regulation, we have no way of knowing whether or not our food contains systemic organophosphates. AQIS carries out testing on only a tiny percentage of imported foods.
Write to your federal Member of Parliament requesting a ban on the use of systemic organophosphate pesticides in local produce, and improved inspections and standards for imported foods. Remind your Member of the cost to the community in treating the problems caused by these pesticides. Where possible, buy organic produce for your children, and grow as much as you can using organic methods. It will not only be healthier – you will notice it tastes better, too.

Strawberry virus

Strawberry crowns sold by nurseries are certified as being free from virus disease. Virus diseases that affect plants are usually incurable, and this is certainly the case with strawberry virus, which is spread by a particular aphid. If you are starting your strawberry patch with crowns from a friend, make sure the crowns are not infected before planting.
Symptoms of strawberry virus are: stunted growth, small and uneven leaf size, and small misshapen fruit. Any plant showing these symptoms should be removed and destroyed. Plants produced by runners (offsets) from infected plants will also carry the virus. To avoid diseases in strawberries, maintain a regular fertilising and watering program to keep plants growing strongly, as stressed plants are less able to resist disease. But, avoid over-fertilising with high nitrogen fertilisers as soft, sappy growth is very attractive to aphids, and may encourage crowns to produce runners instead of fruit. An application of seaweed extract tea mid spring and autumn can help make strawberry plants more disease resistant. Replace plants at least every three years, in a new patch of soil. This will reduce the risk of soil-borne diseases and maintain good cropping, as older strawberry plants are less productive.
Strawberry crowns can be quite expensive. You can purchase some to get you started, and increase the number of plants with offsets after the first fruiting season. Use only offsets from your healthiest plants, planting out during Full Moon phase.