Thursday, September 25, 2014

Backyard chickens may be taking up organochlorines from your soil.

Every now and then someone pipes up to remind or inform other back yard chicken keepers that they may be poisoning their family by letting the chickens free-range in their gardens. This is due to the persistant nature of a lot of the organochlorine type pesticides that were widely sprayed in the seventies and eighties to try and control Argentine ants and termites around people's properties. Often whole suburbs were sprayed, usually along fence lines and back alleys and around the stumps and foundations of houses. If you live in an area that was previously market garden you may be at risk, too. These older established urban areas have more of a chemical load in the soil than the newer suburbs on recently cleared Banksia woodland and sandplain areas.

These chemicals are in a group called Persistant Organic Pollutants. They break down very very slowly and accumulate in the food chain; as each larger animal eats their prey they gather higher and higher amounts of the toxin in their fatty tissues.  If you have chickens and they are scratching the soil and eating insects from an area that is still toxic and then you eat those eggs, there may be some of these poisons in your body. There are a number of problems caused by these toxins, from allergies and neonatal developmental changes to nervous system damage, cancer and even death.

You can reduce the risk of ingestion through eggs by siting the chicken run away from fence lines and house foundations and by installing a cement floor, layers of thick plastic or deep enough fresh soil to prevent the chickens getting to the deeper layers.

You can get your soil tested at various analytical soil labs around the city.
Chemcentre WA is the most commonly recommended.

Monday, September 15, 2014

Five main types of pest ants in the Perth area.

There are five main types of invasive ants in the Perth metro area.

Pheidole megacephala          Coastal brown/big headed ants  
Technomyrmex                      White footed ants
Linepethina                            Argentine ants  
Iridomyrmex spp (various)     Odorous ants  
Ochotellus                             Black house ants 

Firstly you must identify which Genus and possibly species of ant you have.
Identify the type of ant by its looks, food preferences, behaviours, nesting and what potential problems it is causing.
You can use DNA testing but that is expensive and in most cases they can be id'd by looking with an eyeglass or microscope. Close up examination using keys to identify needs some skills and correct information. 

Easiest identification is by observing behaviours etc (above):
*Food preferences: some ants like only sweet foods, some prefer oily foods such as vegetable oil, peanut butter or animal fats.
*Trailing behaviour. Some ants make obvious trails and walk quickly while others meander and seem less orderly.
*Sting or bite? Some ants will do one or the other, others can do both.
*Habitat/nesting type. White footed ants, for instance, will live inside buildings whereas most other ants prefer to live outdoors, only coming in if there is easy access to preferred foods.
*Smell when squashed. Some ants smell more or less strongly of formic acid when squashed and some ants don't smell at all.
*Do they dominate other ants and displace them? 

As with any pest problem always use PHYSICAL or CULTURAL CONTROL first, then least toxic solutions and highly targeted baiting.
This includes removing food sources, keeping benches clean where ants are indoors and finding gaps and sealing them to prevent incursion of the tiny insects.
Big headed ants/coastal brown 
Pheidole megacephala  
These ants are very common around Fremantle. Easily identified by looking to see whether about 10% have large heads compared to the rest of the population of ants present. They have no smell or sting but they can cause a not-very-painful bite. They tunnel under pavers, leaving piles of sand everywhere.
They move into pots and damage plants by eating the root hairs which are high in proteins and sugars. They will also farm aphids and scale for honeydew.They will swarm at foods.
Borax bait using a plain peanut butter and vegetable oil base can be used. A highly succesful target specific product called Amdro works really well.

White footed ants
Smell when crushed and form trails. They don’t sting.
They will live inside buildings  and can appear suddenly in large numbers and then be gone again just as quick.
They will live on sites with other ants species and don't dominate.
These can be difficult to control, needing special baiting repeated frequently as they do not pass poisons to the higher orders but keep it to themselves and make clean sterile eggs for the queen. This means only soldiers die with baiting and thus it needs repetition until the nest is depleted.

Argentine ants
Linepethina humile
Argentine ants are about 2-3 mm long and smell slightly of formic acid when crushed. They have no sting and tend to create regular trails, which they move along slow or fast. They usually live outside and can form super colonies which displace other ants species.
These ants eat sugars and proteins, however sugary secretions called honeydew from scale on plants are a favourite, thus the ants will sometimes 'farm' scale insects.
These ants have multiple queens in each nest and new colonies are created when a queen and some workers move to a new area. Their nests are not always easy to identify for baiting. Least toxic control is by winter trapping of queens. Garden hygiene, removing piles of leaves, sticks etc, can provide less habitable spots for them. Other wise persistence is needed to control this hard to exterminate pest species.

Odorous ants
Iridomyrmex spp
This Genus of ants often move in after coastal browns are removed. They have a strong smell when crushed and no sting. They run riot when disturbed, running all over the creature disturbing their nest. These ants live outside in big colonies and will displace other species.
They prefer animal fats and sugar. Control is by use of targeted baits and DIY options -  2% borax  dissolved in 25% honey or sugar + 73% H2O. Place baits where there are large numbers of ants during their frenzy. 
Ant rid and other target specific ant baits are available in some hardware or pet stores.

Black house ant
Ochotellus spp
Sometimes outside but mostly inside, the black house ants only have a slight smell and are timid, they are easily discouraged by wiping surfaces with eucalyptus oil. They have no sting.
These ants prefer sugar,  and can be controlled using Ant-rid.

If you still don't know what sort of ant you have you could use this service:
Identification service - Department of Agriculture and Food
Correct identification of the pest ant is crucial before commencing any control procedures. There are pest ants that can be more easily controlled based on advice appropriate to that species. A free identification and advisory service is provided by the Department of Agriculture and Food. To submit specimens for identification, stick about a dozen ants to a piece of paper with clear tape and enter your contact details on the paper. Ensure the ants are collected from a clean surface. This will prevent picking up sand and other debris which can allow the ants to escape from under the sticky tape, or spray the ants first with fly spray.

Specimen identification requirements
When sending or delivering samples, the following information is required:
• Collector’s name, location (where the specimen was found), full address, telephone number and e-mail address, description of the damage and date collected.
Department of Agriculture and Food
Pest and Disease Information Service
3 Baron Hay Court, South Perth WA 6151 Freecall: 1800 084 881

Once you know what you have but still don't know how to control the pest at hand contact Systems Pest Management, Fremantle for advice on the least toxic way to control your pest ants.

May 5th 2014 was International Permaculture Day, and one of the talks was given by my old friend David Piggott from Systems Pest Management. He promotes non toxic solutions for termites and ants and willingly shared the information that I used to start these notes.

Some other resources .. 

Sunday, September 14, 2014

Springing towards summer.

Alyogyne heuglii

Chorizema chordatum

Sowed some seeds.

Only sowed a few of each of lots of different varieties
Feeling encouraged by the warmer nights and sunny days, today I sowed a bunch of vegetable seeds. Maybe this year we can get to eat some stuff, instead of the rats pinching it all. I have netted the white shatoot mulberry this year for the first time as we have ravens raiding the loquat tee and rainbow lorikeets back on the powton for their spring flower feast. You get sick of chasing them away after a while.

I'm hoping that if I start beans off here first then they won't disappear like the last lot seem to have done that I planted direct in the soil.
   Also had some success with some cuttings of perennial herbs, which is always a great way to get a few free shrubs. Made a few prostrate rosemary cuttings from a tough self sown rosemary that grows across the road out of a limestone wall. So that should be happy in its new spot up at Ecoburbia.