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Pest Control

 
 
 Monthly Guide for Pest Control

(Extracts from the Fern Society of SA Newsletters)

 

January:

This month is a really good time for the Aphids to appear, the use of Confidor is a good method of irradiation.  Grays Systemic Insecticide comes in a granule form and is good for the irradiation of mealy bug and of scale.  It is very smelly, so you will need to quickly sprinkle the granules around and then cover them with potting mix or soil and then water in immediately.  For scale, any of the White Oils will suffice but not if the temperature is over 25o , however, it is not for use with any of the Adiantums species.  You will need to check for any ants not only on or around your ferns but anywhere in your garden area.

 

February

Watch out for any grey mould on your fine pinnuled ferns, particularly if they are left wet at night.  You will need to stop watering late in the day to overcome this problem.  The autumn days will still mean that the insects are still plentiful, so, if necessary, you will need to spray and you will also need to watch out for any ants.  Beginning to treat these plants for those insidious insects that have taken up residence by importantly using the required logic that is related to the insect breeding habits.  The method of irradiation is to consistently use the systemic insecticide granules every month.  It is very important to include every other plant within a few meters of the infestation, both above and below as well, because these insects are usually quietly hidden in and under these pots as well.  The trick is to immediately cover the area with potting mix and/or water in thoroughly as you pour so you don’t kill yourself too.  Then, alternatively, try spraying or dunking the whole plant with liquid systemic insecticides every 7 to 10 days and repeating the process 3 or 4 times, if, for any other reason you miss a week,  you may have to start again.

 

April

Any moths that are flying around the garden area will ultimately leave a multitude of grubs on the Adiantums and on any others plant for that matter.  These may be sprayed with pyrethrum, carbaryl or any systemic insecticide like Rogor, which may also be used as a spray.  Disulfoton in David Grays System Insecticide in a granule form.  This is an excellent month to report on Adiantums, however, please remember not to overpot.  Using any sprays with an oil base must be completely avoided as these sprays will burn the delicate fronds.

 

July

Any of the caterpillar type pests are often still busy eating your delicate ferns, so you can spray the plants (when the weather permits) and then put out your slug and snail bait because this will only last for a month or so.  All slugs and snails prefer the lettuce type leaves, particularly on your Adiantums plants so leave the bait on the ground overnight and collect it in the morning.  Any of the beer type traps also works very well by leaving the dregs of the beer from the bottom of the bottle from the night before (or any other time for that matter) in a shallow bowl and then collect all of the snails the next morning.  Unfortunately, all of your cold sensitive ferns and other types of plants are at the worst.  Only sufficiently water the plant enough to keep it moist; you can even remove the plant from the pot to help dry it out and/or also remove any saucers from underneath your pots.

 

August

All of the snails and the caterpillars will be on the march, so get those moths first.  You can now add your organic fertilisers like the Rapid Raiser, Dynamic Lifter, Nitrosol or Blood and Bone as it will take about 4 to 6 weeks to work properly.  Wait for the other types of liquid fertilizers until it gets to around the 23o or in the pots that are in the sun and in the high 16o onwards.  If your ferns are yellow from the cold (they are unable to pick up the nitrogen with their roots in the cold alkaline soil) then give them a lift by spraying all of the fronds with a concoction of 50% Season and 50% Nitrosol; this will help things along nicely.

 

September

You will now need to watch out for all of the caterpillars on all of the juicy new fronds on your plants and then later in the month would be a good time to start spraying for insects like the Red Spider, Thrip and the Mealy Bug and then watch out for the ant infestation; dust them to stop the spread of scale to the rest of your garden.

 

October

Again, keep a watch out for the caterpillars on the juicy new fronds on your plants.  Now would be a good time to spray for insects like the Red Spider and the Mealy Bug and watch out for the ants; dust them to continue to stop the spread of scale throughout the garden. Liquid fertiliser time is when the temperature is of 23o and over; a dose now over all of the ferns and in all of the pot will ensure the later good growth of the plants fertilised.  With the onset of warmer weather, the grubs will become more active so further treatment of your plants may be required.  Confidor, being a systemic, is one of the best.

 

November

Now, keep an eye out for scale and stop the infestation of ants with Ant Powder.  If coconut scale is present on any of your Asplenium then the best way to kill them off is with Pest Oil or better still is Eco Oil, but only introduce on a day when the temperature is less than 25º Your Adiantums or Maidenhairs will not like the introduction of Pest Oil at all, so be very careful.

 

Fern Pests

(Extracts from the Fern Society of WA Newsletters)

 

Ferns are subject of attacks by a wide range of pests, however, this should not deter the fern enthusiast as the solution is readily available.  Ferns grown in the ground or in the garden are less prone to attacks by pests and diseases than those grown in containers.  In a fern house, ferns are subject to sporadic attacks from various types of pests, from time to time, as this is an artificial and natural environment, predators are less likely to be present, however, good management of your fern house will keep those problems to a minimum.  Check your ferns on a regular basis and if an attack occurs, assess whether manual removal would be a suitable method or alternatively, use a pesticide that is suitable for curing the problem and if possible, quarantine the plants.

 

It is very important that you use extreme caution when handling any type of chemicals.  For safety reasons, wear a hat, goggles, a pair of gloves, a mask plus a long-sleeved shirt and a pair of long trousers at any time when you are spraying with any form of chemicals.  Make sure that your pets are not in the vicinity of the spraying areas either.  Do not spray when the weather conditions are windy nor should you spray during the extreme heat.  Cloudy conditions are most preferable and it is recommended that you spray during the early to mid morning period for the best results.

 

Note: any pesticides containing any form of Pyrethrum are often touted as being "biological", "organic", "safe", "natural" and even "harmless to humans", however, Pyrethrum, which is extracted from plants of the Chrysanthemum family, are extremely toxic to all animals and humans, if it enters the bloodstream.  Therefore, be particularly careful if you have any skin injuries or any diseases or if you suffer from any allergies.  Always wear gloves and never inhale the spray mist.  Don’t use any agents containing Pyrethrum near aviaries, ponds or if the spraying is likely to come in contact with children or your pets.

 

Material Safety Data Sheets (MSDS).  To find out any information regarding safety in the use of any insecticides, internet research can be conducted by using a search engine and typing in "confidor msds" and you will find pages of the safety information

 

Elkhorn Tip Moth

Damage is caused by a small grub which feeds among the sori of an Elk and/or a Stag.  This grub is the larva of a small, clear-winged moth and it obtains food by tunnelling through the spore patches of these plants and into the leaf tissue itself, causing a browning and the subsequent death of that plant's frond tip.  It also, occasionally, affects Pyrossia species.  Use a Maldison and White Oil mixture or Pyrethrum to eradicate the culprit(s).  Some people place a small amount of systemic insecticides at the tops of Elkhorns, which achieves some success in the eradication of these culprit(s).

 

Passion Vine Hopper

These are a moth-like insect about 10mm across and they have clear brown lace-like wings. The immature stages of this pest are a pale green to white, with a tuft of white hairs on the ends which appear as tails.  They are mainly seen only in the spring to summer period and are very selective.  Spraying your collection with Confidor or Pyrethrum during this period appears to be successful in the eradication of this particular pest.

 

Scale Insects

These insects weaken the plants by sucking out the sap from their stems.  Even when the plants are dead, they tend to remain attached to the plants for a long period of time.  They are easily removed by hand or alternatively by spraying the affected plants with a mixture of Malathion and White Oil on a cool day.  The systemic insecticide Disyston is also an effective method of eradication. 

 

Waxy White Scale (Gascardia destructor)

These pests are found on the stems and branches of many plants, including citrus, Gardenias and Camellias.  They mainly attack the Cyathea and Dicksonia (Tree Ferns).  When squashed, they exude a sticky pink or red fluid.  Control is by Malathion or White Oil mixture, systemic insecticide or removal by hand.

 

Soft Pink Scale

This is a rather large pest compared to other Scale.  It seems to attack mostly Woodwardia species.  It has also been seen on ivy.  Spray with Malathion and White Oil.

 

Coconut Scale

This pest feeds by sucking on the undersides of fern fronds and it gets its name from its appearance, which is akin to desiccated coconut.  It is fond of Asplenium species, Nephrolepis and Tassell ferns.  Control it with applications of soapy water or a Malathion and a White Oil mix, also with a systemic insecticide.  Follow-up spraying at ten-day intervals is recommended.  Coconut scale will remain on plants for long after it has been killed.

 

Thrips

These tiny insects graze on the surfaces of young fronds and they seem to be particularly fond of the Todea Barbara, Polystichum, Doryopteris and Dryopteris species.  Control these pests with Maldison, Pyrethrum, Confidor or a systemic insecticide.

 

Slugs and Snails

The slugs and snails will cause damage to new fronds and emerging fronds by chewing them and they are particularly active in wet conditions.  They feed mainly at night and they may be removed by hand or killed by any water-resistant snail baits.  Use caution with regard to other animals, which may be poisoned by the baits.

 

INSECTICIDES – MAKE YOUR OWN

 

Clensel:

A soap based spray, use 100ml in 2.5lt of water; this kills aphid, thrips and spider mites.

 

Natrasoap: 

Kills aphids, thrips, mealy bugs, scale, mite and white fly, at the rate of 10 to 20ml per 1 litre of soap spray

Potassium oleate, (olive)

Potassium linoliate, (linseed)

Potassium palmiate (Palm)

Potassium stearate (mineral ???)

These two are very safe and if used on fruit or vegetables the produce can be washed and eaten after 1 day.

 

Methylated Spirit:

Use one (1) litre of water and 2 cups Methylated Spirits (1 cup equals 250ml)

Before using, test on a few leaves first as it will burn some soft plants.  Used for scale, mealy bug, white fly and aphids.

 

White Oil Pesticide

A Pest oil that controls scale, aphids, mites (russet), mealy bugs, citrus leaf miner, spider mites.

 

Fish Emulsion:

This will work on spider mites.  Soak 3 to 4 ounces of chopped garlic bulbs in 2 tablespoons of mineral oil for one day.  Dissolve 1 tablespoons of fish emulsion in a pint of water and add it to your solution.  Stir well and strain the liquid and store in a glass containers – not metal! Dilute one (1) part of this solution to every 20 parts of water.  This will kills aphids, mosquitoes, and onion flies.

 

Milk for Mildew:

Milk is another very effective spray for powdery mildew.  Mix the milk at a ratio of one (1) part milk to nine (9) parts of water and spray weekly.  Do NOT go higher than 3 milk to 9 water or you will attract other fungus problems that want to feed on the milk.  Skim milk works well as it contains no fat to turn rancid (and attract other problems that like the smell of rotting fats.)

 

Make your own insecticide from Bracken fern (Pteridium esculentum):

Place three (3) firmly packed cupfuls of chopped bracken fronds into the bottom of a large saucepan and just cover with one (1) litre of water and bring to boil.  Cover and simmer for ten (10) minutes.  Cool and then strain.  Use this mixture within the next few days.  This is a potent spray so handle it with extreme care.  It will deter aphids and bean fly and cockroaches will eat the leaves and then die.

 

Recipes for Alternative Pesticides

 

Garlic:

This is used as an insecticide and fungal control.

100ml minced garlic

10ml mineral oil

500ml water

50ml soft soap

then soak the garlic in the mineral oil for two (2) days, then add the water and the soap. Strain and store in a glass container.  Use at the rate of 1% solution (1 part of 99 parts water).

 

Herbal Sprays:

Many herbs can be used as insecticides and insect repellents.  The formula to use the herbs is to just cover the fresh herbs with boiling water, then steep for 30 minutes.  Now strain and dilute with an equal quantity of water.  As the potency of the herbs will vary depending on season and other conditions, exact recipes are not possible.  The addition of soft soap as a wetting agent will increase the effectiveness of these materials.  Wormwood, southernwood, tansy, chamomile, rhubarb leaves, ragwort, potato leaves and lantana are all worth trying.

 

Soap Solution:

This is an effective aphid killer.  The best soap solution to use is potassium soap, also known as soft soap.  Being a liquid, it is easier to dissolve.  Two commonly available brands from most nurseries are ‘Clensel’ and ‘Safers’.  To mix, use 100ml per 2.5lt of water.

 

NOTE:

It is important to remember that when you need to spray, assess the situation first.  If you have pests on only a few plants, spray only the affected plants, preferably removing them to another spot to do so.  If the situation has become overwhelming, then it is probably best to spray all of the plants in your shade house if it means saving your collection.  However, you must also consider the predators that are likely to be doing some work for you in the background.  If your shade house is well managed, you probably will have frogs, praying mantis, mud wasps, dragonflies, ladybirds and feathered birds present.  If we interrupt the food chain, the pests will dominate.

 

Somewhere, we need to strike a happy balance.

 

 

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