|Back to Back Issues Page|
Aphids, What You May Not Know.
May 20, 2013
Prayers continue for the areas devastated by tornadoes and other weather conditions.
This past week's Monday morning brought a hard frost and freeze.
Many plants show the ill effects of frost damage.
Hydrangea and Hosta come to mind.
Since then, the weather has been rather nice on the most part.
Temperatures a bit above normal and lots of sunshine.
And wouldn't you know it.
After the floods of April, we are in need of rain, as I find myself have to turn on sprinklers already.
Not to mention record numbers of mosquitoes.
Before I forget.
Next week Monday is Memorial Day here in the U.S. of A.
As in years past, the newsletter will be delivered on Tuesday, and not Monday.
We all need time to remember our Heroes, and take a little rest.
The intoxicating aroma of lilac fills the air.
When the wind blows just right, a person can almost drift away with the soothing smells of lilac in bloom.
Walking around and finally checking things out, I find that I have lost several perennials this past winter.
Many of my Echinacea are no more.
Cultivars like Tiki Torch, Hot Papaya, Coconut lime, etc. died off.
As did several of my Columbines, and Hyssop.
Plants that are Zone Hardy, but when a stretch of sub zero temperatures come along in February, and there is little or no snow cover, crowns freeze and die.
It is well known that snow is a very good insulator.
It really needs to be welcomed in northern gardens.
Birds are busy around here, as I'm sure they are in your location too.
This fledged robin gives you an idea of the action taking place.
This poor little guy/gal ran into a neighbors house and was stunned.
So much so, it could perch on a branch at all.
Mom and dad were loud and keeping an eye on me.
Only a couple of White-crowned sparrows remain, as they continue the journey into Canada and their breeding grounds.
I will miss the happy calls they seem to make.
Orioles are still entertaining us (we have 4 different feeding stations).
We finally have hummingbirds.
A female graced the feeder May 16 and continues.
We haven't seen a male Ruby-throat just yet.
No matter, spring is now complete in a manner of speaking).
No matter where you live, if you experienced drought conditions the last year or two, you probably notice or have noticed something.
Many trees and shrubs have produced a plethora of blooms and catkins this spring.
With blooms will come fruits, cones, seeds, and acorns.
You may notice the whirlybirds falling and growing on Maple Trees.
Flowering Dogwood are exceptional this spring.
Not too often will they bloom like they are this year.
Look at your conifers.
Are they growing more cones than usual?
This fall and into next year, you may have a bumper crop of acorns.
Why you ask?
Nature has given plant life a survival mechanism.
When there is a drought or a plant is stressed one year (last year), the following year it will produce an abundance of seeds.
This is to insure the survival of the species.
A few stressed year in a row, and trees, shrubs and flowers begin to die off.
The only way to insure survival is to reproduce in masses.
Some seed will surely survive.
Bumper year like this one, also means bumper crops of mast (seed, nuts, fruits) for wildlife.
Prompted by comments some of you have made, I am attempting to tackle the issue this week.
What you may not know.
Aphids (Aphis gossypii):
They seem to be pretty thick in some regions this year.
Even The Mall of America is under attack from millions of the little suckers.
To counter attack, the Mall has introduced 72,000 Ladybugs or Lady Beetles to feast on the aphids.
The real attack comes from the Ladybug nymphs.
About 4,400 different species. Most species feed on only a single type of plant.
They tend to infest those plants and they can be very destructive.
Most aphids only live for about 20 to 40 days, but it gets interesting from here.
As individuals, they do little harm to a host plant, but large infestations can produce severe damage.
Their behavior is determined largely by food preference and feeding site.
It can generally be said that anytime you observe large groups of very tiny insects hanging onto a plant, they are most likely aphids.
Most are seen on the leaves, stems, and foliage of plants, especially on the new growth, but there are species that feed underground on roots and bulbs.
Many produce galls or other deformities.
Thankfully, there are many effective control methods available.
A soft-bodied, pear-shaped insect, the aphid is generally very small, with most species under 1/8 inch in length.
Aphids can be almost any color, but green, black, white, and gray are the most common.
Some are covered with a threadlike white material, which makes them appear woolly, while others may be covered in a fine dust.
There are both winged and wingless individuals of most species. Aphids can be identified by a beak or rostrum that sits far back on the underside of the head.
Their antennae are rather long and placed in the front of the head, between the eyes.
The feet are two jointed and terminate in claws.
Many aphids have a pair of projections called cornicles on each side of their body.
Life Cycle and Reproduction:
Now this is stuff you may not know.
I learned this about 15 years ago as part of my continuous education to remain a 'Certified Nurseryman'.
Aphids live in large colonies and reproduce rapidly, having numerous generations each season.
The reason a bazillion aphids seem to be born overnight is because they are – literally.
Here’s the thing, aphids are all female.
Every lady aphid is born pregnant.
You just have to wonder what they did so wrong to deserve that.
While they are born pregnant, they don’t actually give birth until they are a mature adult - which is about ten days after their own birth.
In the warm temperatures of spring, out of the over-wintering eggs emerge the female aphids called “stem mothers”.
The stem mothers give birth to live daughters, who are also pregnant.
In actuality, aphids are born pregnant.
Mothers give birth to daughters, that are already pregnant.
(Is this a form of cloning?)
In a manner of speaking, Mother is not only birthing her daughters, but unborn granddaughters as well.
(No candlelight or romancing necessary.)
In other words ....they don’t need a male.
It’s really a superior race of women gone terribly wrong.
This odd phenomenon continues with every generation of girl aphid until the end of the season.
These nymphs mature quickly, molting about four times (you may notice what looks like shells of dead aphids mixed in) over seven days before they start producing their own clones within 10 days.
This is where it gets interesting.
At this point, the aphids begin to produce daughters and sons.
These sons mate with the current generation of female aphids and those females lay eggs on bud scales to over-winter.
Thus, the freaky cycle begins again.
After several generations, wings form after they are born and fly off to other plants.
They don't actually fly, but are blown by the wind.
Males are produced in the fall, at which time mating does occur and females lay eggs that overwinter in bark or ground litter.
Larvae will emerge in spring.
On average, an aphid lives for about one month and each female can produce 80-100 offspring in a week (You do the math).
Aphids have many generations each year.
An aphid feeds on its host plant by sucking plant sap through a beak-like feeding tube inserted into plant tissue, thereby weakening stems and leaves.
Check the undersides of leaves for small groups of aphids, or you may find them clustered on the new buds, stems, and young leaves of flowers.
Another flag that may alert you to these ladies’ presence is a long ant trail, which much like groupies, seem to worship the ground the aphids walk on.
The reality is that while the aphids suck the life out the tender greens on your plants, they are secreting a sticky-sweet substance called “honeydew” that the ants
Hence, their tireless pilgrimage up and down every plant that may host an aphid.
These ants, in turn, may kill any aphid predators.
Ants will often bring aphids to plants by carrying them through their tunnels to plant roots, and will nurse aphid eggs through the winter.
Infested plants often show distorted growth that may be curled, puckered or otherwise stunted.
Leaves may show pale or yellow spots or entire leaves can turn yellow or brown.
Flower buds and flowers may also become shriveled or reduced in size.
New plant growth may be twisted.
Under bright sunlight, affected plants will often wilt. Seedlings and tender ornamentals can be severely damaged by an infestation of aphids.
Some aphids do live underground and suck the life from roots, bulbs and corms.
The only way to verify their existence is to examine the roots of plants for knots caused by these aphids.
Besides the knotted roots, plants infested with root aphids show the same symptoms as those attacked by the above ground species: stunted and wilted growth, with curled, yellowed foliage.
Root aphids damage bulbs by sucking out nutrients and causing wounds through which fungal and bacterial decay organisms can enter.
Badly infested bulbs will produce weak and stunted growth and yellowish leaves with brown tips.
Those flowers that do mature are usually small, streaked and off-color.
If a plant stops growing, it may be a sign of root aphid infestation.Control:
An aphid problem may often be a symptom of too much nitrogen fertilizer or an overuse of pesticides that have eliminated natural predators and parasites.
Changing to organic, slow release fertilizers and non-toxic pesticides, and encouraging the natural aphid predators listed below, are important steps in reducing aphid populations.
Aphids are attracted to the color yellow.
Fill a yellow container with slightly soapy water, or place a yellow board covered with a commercially- formulated “goo” near susceptible plants to serve as traps a week or two before aphids are expected to appear, usually in early May through June.
Certain plants, such as nasturtiums, petunias, garlic, coriander, anise, chives and other alliums can act as ‘target crops’, attracting aphids away from more vulnerable plants.
Aphids deposit eggs in leaf litter and twigs, so good garden sanitation in the fall and a thorough clean-up of flowerbeds in spring will help to eliminate sites where eggs may overwinter.
Make sure air can circulate around vulnerable plants; stagnant air creates a more attractive environment for infestations.
Another good practice is to encourage winter songbirds to visit your garden because many birds will search tree bark for overwintering aphid eggs.
Aphids aren't a huge issue for me, i like to keep some leaf litter for insulation and for the birds to forage in.
Good varieties are chickadees, nuthatches, purple finches, and warblers.
A thorough control of aphids means controlling the ant population as well.
Establishing barriers of cinnamon, or a powdered charcoal is an effective method, and cleaning up leaking tree sap will detract ants.
A side note:
The use of banana peels is effective at keeping aphids away from roses, it works for me and this year i will be using banana peels around other aphid loving plants as well, to see the peels work around other plants.
By the time you notice an aphid problem, they are usually too numerous to effectively control by hand removal.
Light infestations can be controlled
For best results, spray every other day for a minimum of at least three times to effectively decrease the population.
Fortunately, aphids have many natural enemies that are very effective in controlling infestations.
Chief among these is lady beetles, with both adults and larvae usually increasing in number to thoroughly control the damaging population.
Other major predators include lacewings, small parasitic wasps, syrphid flies (hover flies), and soldier bugs.
Avoid the use of any chemical sprays while predators (birds and insects) are present.
Insecticidal soap, such as 'Safers', is an effective control method and is less environmentally toxic than other chemical sprays.
Apply thoroughly to the plant every 3-5 days over a two week period to eliminate the infestation.
Foliar insecticides may be applied if aphids become numerous and continue to be a serious problem (last resort).
Check for the presence of lady beetles and other natural predators before spraying any insecticides.
You may check with the proper agency on what products are best.
Use pesticides safely and wisely; read and follow label directions.
Well,, it is time to fly for now.
Before i go, here is your positive thought for the week.
(Tree Swallow on neighbor's dish.)
"Those who dwell among the beauties and mysteries of the earth are never alone or weary of life."
Beauty, mysteries, nature.
What can a person add to such a wonderful quote?
"For by him all things were created, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things were created through him and for him. And he is before all things, and in him all things hold together."
"Treat the earth well:
It was not given to you by your parents,
It was loaned to you by your children.
We do not inherit the Earth from our
Ancestors, we borrow it from our Children."
Ancient Indian Proverb
Your friend indeed,
Better yet, have them sign up so they can receive their own letters.
|Back to Back Issues Page|