GOOD VIBRATIONS
Posted by Phytopath on Jun 26, 2011
Remember that song by the Beach Boys back in the mid 1960’s?
The fact is – insects knew about good vibrations well before the Beach Boys.
Many insects, including cicada, ants, beetles and stink bugs, use vibration to attract sexual partners.
Not much difference to the disco days, when we all gathered at a particular venue to ‘check each other out’ on the dance floor.
Experiments performed by biologist Andrej Cokl on southern green stink bugs, showed female stink bugs provide detailed directions to their male suitors, on where to find them.
This AGPS (Arthropod Geographical Positioning System) uses vibration as its method of transmittance.
Initially, the male releases pheromones to attract the female.
Scent or aroma is not always a precise indicator of the origin of that aroma (unless it is a dead mouse under the refrigerator), so the female sometimes lands on a nearby plant instead of the same plant the male is eagerly waiting upon.
Once the female has landed in the nearby vicinity of the male, she starts to vibrate and send out a type of Morse code, tapping directions to the nearby male.
Cokl noticed that female stink bugs moved an abdominal plate attached to the thorax, in time with the rhythms oscillating through plants (100 hertz pulse every five seconds).
These vibrations move through the plant at speeds between 30 and 100 metres a second.
Flavio Roces of the University of Wurzburg in Germany believes that the difference in arrival time of the vibration between the left and right leg of the stink bug, is an indicator to the bug whether to move left, right, up or down along the branches of the plant.
He also believes that mechanoreceptors on the antennae may also play a part in determining which direction to go.
This constant movement of legs and antennae on the plant must certainly look like a disco dancing dude.
A truly amazing sight.
photo from Wikimedia commons
Gardening can be Dangerous
Posted by Phytopath on Oct 22, 2010
I was prompted to write today’s blog post after a visit yesterday by a brown snake taking a drink from my fish pond.
I regularly enjoy gardening activities, especially weeding because you don’t have to think too much and can just day dream while enjoying the warmth of the sun.
Complacency can be a threat to your health and well being in this great country.
Australia has a mighty impressive list when it comes to venomous snakes.
A great website (www.deadlyaustralians.com.au) lists information on Australia’s not so friendly fauna.
According to the website, of the World’s most venomous snakes, Australia has 20 of the top 22 in order of lethal potency, and number one to number eleven are Australian. That means that Australia has the top eleven deadliest snakes in the world.
From this list of 22 deadly snakes, four have been seen on my property and I still, pull knee- high weeds without wearing gardening gloves. (I think I’ve been in the sun too long).
The common brown snake (pictured here in my pond) is the World’s second most venomous snake. It grows to around 1.5 metres (5 foot something) long but some have been seen to grow up to 2.3 metres long (seven foot something).
They are usually found in dry areas and feed on mice, rats, frogs, small birds, lizards and other snakes. They lay up to 35 eggs which incubate for six to eight weeks.
Shortly after they hatch my cats seem to find them and bring them to the house to play with before eating (see photo). I always have to remember to keep the door closed to the house during summer or the cats would bring them inside.
Two of my cats have been bitten by brown snakes over the years. The first cat cost me around $500AUD at the vet for the anti-venom and an overnight stay (about four or five years ago). The second cat managed to survive the bite by lying very still for three consecutive days without eating or drinking (moving around too much pumps the venom through the system quicker).
Some cats are able to overcome the effects of the snake bite, if they have a lot of fur and the snake does not get a good strike, but most dogs are just too stupid, and they keep running around to pump that venom through their veins.
Another snake found on my property is the Tiger snake, the Word’s 4th most venomous snake. These snakes are frequently found near water and average about one metre (3 feet) in length.
Tiger snakes can be territorial, so if you see one, expect that they will probably hang around for a while. They are also nocturnal during warm weather (late spring, all of summer and early autumn), so no walking barefoot in the garden on a moonlit night. Oh – they are also aggressive and will attack if they are disturbed (must all be females, haha).
I recall a time when my girls were younger; having to calm them down after a tiger snake chased them when they were catching yabbies in the creek at the back of our house.
They feed on frogs, fish, small birds, rats, mice, lizards and other small animals. Their litter can be up to 60 young but more commonly around 35.
A visitor to my front door last summer was a red-bellied black snake. They are not as venomous as the snakes already listed, but still, I wouldn’t like to be bitten; the bite can be fatal if untreated.
As the name suggests, they have a red under belly and are shiny black on top (quite pretty really). Normally found near a source of water, they grow to around 1.5 m or 2.0 metres long (just over 6 feet).
They are not aggressive but will strike if they feel threatened. You can find them under timber and rubbish or down a rabbit hole (not that I am looking for them) and their preferred food is frogs, but they will also eat lizards, small mammals and other red-bellied black snakes (charming).
The introduction of the cane toad into Australia caused a decline in the number of red-bellied black snakes because the poison in the frogs was enough to kill the snake. Over time the snakes have become aware of this and now have altered their diet from frogs to rodents.
I read recently that Australia has 130 land-dwelling snakes, 70 of these are venomous and 25 of the 70 can cause death to humans. They don’t tell you that in the promotional material aimed at overseas visitors coming to Australia.
Anyway, I was going to talk about deadly spiders in the garden as well, but this blog post is becoming a bit lengthy, so I will mention them next post.
Happy gardening.
Chemical Alternatives
Posted by Phytopath on Jun 26, 2010
Thanks to the World Wide Web, today’s gardener has access to far more information than gardeners of 50 years ago. I believe today’s gardener is also more aware, when it comes to garden chemicals.
We have choices. And if you choose to try some alternatives when it comes to tackling pest and disease problems, here are some simple solutions. Keep in mind that these solutions probably won’t work as fast as their chemical equivalent and may need several applications rather than one dose. It also does not imply that these recipes are ‘safe’ just because they are home made. Treat them with respect.
Heavy infestation
SOAP SPRAYS
are frequently used for soft bodied insects like aphids. They should only be applied with low pressure because under high pressure, with an atomiser, they can be a health hazard.
Soap sprays can also damage plants and soil when used in excess. Regular use on plants can break down the protective waxy coating on plant leaves, a bit like breaking down the skin on our bodies or the paintwork on cars – not a good practice. Do a test spray first. Try one or two leaves and leave it for a few days to observe the results before spraying the whole plant.
Choose a soap that is made from caustic potash and not caustic soda or use a ‘Pure’ soap. Grate about 60 grams of the soap (with a cheese or vegetable grater), into a nine litre bucket of water, then swish the water until it is frothy. Pour into a watering can and spray on to affected plants.
End of Season
SOAP and BAKING SODA (BiCarb Soda)
can be used as an anti-fungal spray. Try using it against downy mildew, black spot and fungal rusts. Again, be mindful of human and plant protection. Do a spot test (on the plant, not yourself) and cover up, especially the eyes, when using the mixture. Also, do not use on a hot day.
Dissolve about 150 grams of baking soda in the 9 litre bucket of water, and then add the soap (60 grams). Use as described above.
Scale
COOKING OIL
is often used to make a white oil solution to treat scale insects. Never use this spray if the temperature rises above 24°C (75°F) and stays there for three or four days after spraying. For some gardeners, that will mean NO spraying during the summer months.
Add one cup of water and two cups of cooking oil to a blender and mix until you get a milky white solution. This is the ‘concentrate’, which is then diluted with more water at the rate of 20 to 70 ml of concentrate per litre of water. This mixture separates out quite quickly so must be used strait away. Do not make any more than you need for an application.
MILK SPRAYS have been used as a chemical alternative for black spot on roses, for – like – forever. Does it work? That depends on who you ask. The milk and water spray has a number of uses, but the main use is, as a fungicide. It is also apparently a good spray for treating mildew on cucurbits.
Mix one part real full cream milk with nine parts water. Some people suggest a ratio of 50/50, equal parts milk and water. Experiment a little and see what works for you. Spray with a watering can or atomised sprayer but remember to always wash the container thoroughly afterward. Off milk just smells – well – off.
MILK and FLOUR can be mixed together to make a spray against red spider mite, two spotted mite and azalea lace bug. Mix four cups of flour with a quarter cup of milk, pour in to a baking dish, oh, sorry wrong recipe.(My attempt at humour).
Mix four cups of flour with a quarter cup of milk then add mixture to 20 litres of water, stirring constantly until well mixed. Spray on to all surfaces of the plant and repeat every two days until symptoms subside (critters disappear). Wash equipment well.
SUGAR, most people’s addiction, is used as a soil drench to control nematodes. Dissolve two kilograms of sugar (I don’t think the nematodes mind which sort) in ten litres of water. (a great syrup for preserving fruit) and pour over the soil where there is suspected nematode activity. Although this drench works to destroy nematodes, unfortunately it will have the same effect on worms and other soft bodied soil life. Use at your discretion.
SALT is a great weed killer but don’t go there. It is very bad for the soil. Use boiling water instead.
If you have any other gems that can be used in the garden instead of chemicals, let me know.
Pest repellent plants
Posted by Phytopath on Jun 11, 2010
Pests
Plants that have the ability to repel pests (whatever that means to you – and no, it doesn’t include your spouse), come in various shapes and sizes.
Plants grown in the garden for pest control have some advantages over commercial sprays. First being, no chemical spray drift onto desirable plants or neighbours gardens.
Not all insects in the garden are pests and some are even beneficial. Many of the insects do little harm and actually feed on other insects that are pests.
Pest repellent plants can mask the scent of targeted plants from invading insects. If you have a favourite plant that is constantly being attacked by insects, try planting some heavily scented plants next to or nearby the vulnerable plant. The attacking insects will not be able to ‘sniff out’ their prey.
Apart from confusing insect pests, some pest repellent plants will actively repel them. Try planting several around the garden or vegetable patch.
You may also like to plant a variety of plants in the garden that attract predators, like ladybirds and lacewings, to help control the bothersome insect pests.
Biodiversity in the garden is a wondrous thing.
Some of these plants are also useful for making sprays, but always be mindful of your actions.
Dogbane (Plectranthus ornatus, Plectranthus caninus) is a strong smelling perennial ground cover, growing to about 15 cm when not in flower and around 30 cm high when in flower. The flowers are a pale lavender colour and occur mostly in autumn. The leaves are fleshy with hairs on the upper surface and they have a very strong odour. The common name comes from its apparent ability to repel dogs, but not all dogs are affected. The plant reputably repels a range of pests in its vicinity. Give the plant a warm protected position away from frost. Once established, it requires very little water.
Cotton lavender (Santolina chamaecyparissus) is another plant used as a pest repellent. Its main use is in repelling moths and silverfish. The plant is a small shrub to around 50 cm high with grey foliage and yellow flowers during summer. The fine leaves are aromatic (and don’t stink like dogbane) and can be dried and placed in sachets to repel moths in linen cupboards and wardrobes. The dried leaves can also be used to repel silver fish. Just scatter them on the bookshelves or place many small sachets behind books. If that does not work, try blending 50 ml of white vinegar with 50 drops of lavender essential oil, 50 drops of peppermint essential oil and 50 drops of citronella essential oil. Place in a 350 ml spray bottle and add 250 ml of water. Shake well and use on a cloth to wipe down bookshelves, once per week.
Marjoram and Oregano, (Origanum spp.) known for their culinary use, can also be used to deter pumpkin beetle from nearby cucurbits. They are also useful in protecting onions from maggot and brassicas from the white cabbage butterfly. Choose a variety that will grow well in your area.
Wormwood
Wormwood, (Artemisia absinthium) has long been used to repel lice on chickens by planting a hedge around the chicken coup. The plant can have a negative effect on nearby plants by inhibiting their growth, so choose their position in the garden carefully. The active ingredient in wormwood is thujone which adversely affects the nervous system. For this reason it is no longer used in the drinks: absinthe, pernod or ricard. It can however, be used to repel aphids, whitefly, bean fly and some caterpillars. The fresh leaves can also be used to repel fleas on your pet, by rubbing them through the animals coat. The leaves can also be dried and powdered and used to repel ants, thrip, moths and flies.
What a plant.
This is just a very short list of pest repellent plants. There are many more to choose from and I am sure you will be able to find some that will grow in your climatic conditions.
Critters – Friend or Foe?
Posted by Phytopath on Jun 8, 2010
Hmmm...
Are you constantly annoyed by bothersome pests on your favourite plants and vegetables?
Do you head straight for the spray container, eager to fill it with the latest chemical or organic spray?
Why?
Gardeners have been trying to eradicate pests for as long as they have been gardening. Millions of dollars have been spent on chemicals, helping to increase profits of chemical manufacturers, for what?
The pests seem to re-appear again next season or next year. What about the effect on the food chain? If you eradicate one pest, even temporarily, you will change the feeding habit of the predator, perhaps even decreasing its numbers, and on it continues.
Have you ever considered welcoming the so called pest and fostering bio-diversity in the garden?
Imagine having an array of butterflies to watch as they dance around your garden, because you didn’t spray the caterpillars. Or an assortment of bugs for children to wonder at, with their different shapes and colours, because you didn’t spray the grubs.
If you have certain vegetables or a favourite plant that is constantly being attacked, look at the growing conditions. Is the plant in the optimal position for sun or shade, drainage and frost, buffering winds, salt spray etc. etc.
If the optimal growing position is not supplied, move the plant, if you can. If the plant or vegetable cannot be moved, think about planting sacrifice plants.
Pests usually seek out the weakest plants first, so if its cabbages (for example) that you are having problems with, plant a couple in the garden where they will not grow at their best. Make sure it is away from your desirable plant, or the vegie patch, and hopefully the majority of the pests will attack the weaker plant rather than the one you are eye-balling for dinner.
Better still; plant some native plants (to your area) that will encourage predators to your garden, to help keep the pesky critters under control.
Do you really need control for twelve months of the year? Some of the pests that visit your garden, may only pose a problem two or three times a year.
Learn tolerance. What is so bad about sharing some of your produce with others? Even if the ‘others’ are perceived pests. Minor damage to a piece of fruit or a vegetable will not affect the taste. Learn to accept small losses, knowing you are creating a diverse habitat in your garden.
Citrus Pests
Posted by Phytopath on Apr 20, 2010
Kumquat
You are very fortunate if you can grow citrus plants in your garden without them being affected by pests.
I have listed some of the more common pests below.
Black citrus aphid is usually a problem on young citrus trees. They are seen on new growth, mainly in spring and if severe, can cause stunted growth and the production of honeydew, which can then develop into sooty mould.
If ants are detected, they must also be dealt with because they can disrupt the control of black aphid by natural predators. The aphids multiply rapidly and early detection is important.
Both biological and chemical control can be used on Black aphid. Biological control usually occurs naturally by early summer and is obtained by encouraging natural predators such as ladybirds, hover fly, lacewing larvae, birds and parasitic wasps.
Scale. Many types of scale attack citrus trees. Some are: – red scale, soft brown scale, black scale and cottony cushion scale. Red scale is the most common and usually causes the most damage to trees. The other three types of scale are normally controlled by natural predators.
Red scale are very small insects that have a waxy covering that is circular in shape and reddish brown in colour. Infestations can cause blemished fruit, split fruit and fruit fall. If the infestation is particularly severe, it can cause stunting of the tree and even death. As many as 45 nymphs are produced per female. They prefer warm, dry conditions followed by autumn rain.
Control can be achieved by spraying the tree in mid-summer with a ‘summer spraying oil’. Make sure all of the leaves are thoroughly covered by the oil, which suffocates the scale. Follow the directions on the label or, if making up your own spray, make a two per cent solution of oil in water and stir the mixture constantly while spraying to avoid the oil/water separating.
Sooty mould looks just like the name says – soot. It is a black powdery substance on the leaves and twigs, and sometimes also on the fruit.
Sap sucking insects (that’s like plant vampires), such as aphids, mealy bugs and whitefly larvae, are the cause of sooty mould. They excrete (eewww) a sweet, sticky, honey-dew, and the mould grows and feeds on this.
Ants like to transport aphids, which helps in the spread of the honey-dew, so it is important to control or treat the ants when they are seen on or around the affected trees.
Mites of various types may also infest citrus.
Citrus rust mite causes damage on immature fruit during summer and autumn. It prefers humid conditions with temperatures below 35°C. Heavily infested fruit appears to have a coating of dust which is actually the mite and its castings.
Broad mite attack can cause leaf edges to curl under, and the under-surface of leaves to go a bronze colour. Fruit that is situated lowest on the tree are affected first.
Citrus red mite, are 0.5 mm long and dark red in colour. Their presence causes leaves and immature fruit to lose colour and appear pale, with leaves eventually falling from the tree, starting at the top.
Natural control can occur if weather conditions change or if there is a high number of ladybirds.
Creating an environment for natural and beneficial predators is always helpful in the control of any problem pests.
Ladybird larvae
.
Dragonflies – cont.
Posted by Phytopath on Jan 27, 2010
Now that I have regained some composure, I will continue with the article.
Dragonflies have the ability to see stationary objects 1.8 m (6ft) away and if the object is moving, they can see that object up to 5 m away.
Their legs, six in all, are covered with spines and are used to capture prey in flight.
The dragonfly can also eat it’s prey while flying (true take away).
Their flying speed can reach 80 to 97 kmph (50 to 60 mph)
The adult dragonfly lives for only a few weeks to a few months, it’s main purpose to find a mate and produce offspring.
The young nymphs remain in a watery environment for one to five years and molts about 12 times before leaving the water to shed it’s skin for the last time.very fortunate to have my interlude with the dragonfly in it’s very short time as an adult.
Dragonflies
Posted by Phytopath on Jan 25, 2010
As I was enjoying the garden yesterday, a rather large dragonfly ‘buzzed’ me.
A bit optimistic, I thought.
I am used to seeing those beautiful blue damselflies in and around the garden and fish pond, but I rarely see dragonflies.
So off I went inside the house to do some research on dragonflies.
It turns out that dragonflies have all-around vision, some having 28,000 single lenses in their large compound eyes, and they like to eat flies.
Oh, and the nymphs have gills inside the rectum. ewww, gross. The mind boggles.
But wait, there’s more.
If a dragonfly nymph is under attack from a predator, it can squirt water under high pressure, from said gill, out the end of the abdomen.
This jet propels the dragonfly nymph away from the attacker. OMG I have a mental picture now.
At that point I had to close the book so I could roll around on the floor laughing.
By now, I not only had a mental picture of jet propelled, water squirting, dragonfly nymphs but also a picture of my flatulent producing friends skimming around water holes.
It’s time to stop the pictures.
Dragonfly
