Tuesday, January 26, 2016

Aphid Control on Fruit Trees

Aphids are one of the most well known garden pests. They are easily identifiable when they congregate on young tender plant tissues. Aphids pierce their hosts and suck the nutrient rich sap causing damage or even death to your plants.

Aphids can be found in many colors, grey, black, green, and brown. The color of the aphid in many instances correlates with the aphid's preferred host plant, camouflaging them from plain sight. They will often hide on the under side of leaves allowing them to get a strong hold on plants before they are discovered.

Aphids on a Spring Rose Leaf
Aphids can be winged or wingless depending on their age. Winged aphids are able to travel long distances in search of new food sources. Most of the aphids found in your garden will be young female nymphs without wings. Even though they are not fully grown, aphids can reproduce, and they can do so without the presence of a male aphid. This is why they seem to magically appear over night!

Aphids Multiply Quickly and Seem to Appear Overnight
Aphids are a favorite food source for lady bugs, lace wings, and other beneficial insects. Aphids excrete a clear sticky substance called honey dew that is also coveted by other insects, some of which are less popular than lady bugs. Wasps and ants will swarm aphid infested plants to feed on the honey dew covered leaves and branches.


Aphids are an Important Food Source for Many Beneficial Insects
The presence of an aphid's natural predators is one way to determine if fruit trees need further inspection. Also, the honey dew that these insects excrete is often identified by gardeners before they discover what is creating the sticky film over their tree's leaves and branches.

Honey Dew is a Clear Sticky Substance Excreted by Aphids
Wasps Feeding on Honey Dew is One Way to Identify an Aphid Infestation
In the ecology of insects, aphids are like helpless swine whose sole existence is to eat, grow, and multiply quickly so the insects higher on the food chain can feed their voracious appetites. With that being said use of chemical and organic pesticides may eliminate your aphid infestation, but it will also kill off the swarms of beneficial insects that have come looking for an easy, nutritious meal. 

The best way to treat fruit trees for aphids is water. 

Water?

Yes, water!

Water at high pressure will wash away the majority of the aphids infesting your fruit trees along with the honey dew. True, the beneficials will be washed off as well, but they will quickly return to finish off any aphids that managed to hold on. The aphids that fall to the ground by your efforts either lack strength or brain, I'm not sure which, to return to their host plant and will quickly die of natural causes.

Make sure you aren't using water pressures that will damage your tree. A hose with a good nozzle will suffice. There is no need to defoliate your tree with a high powered pressure washer. If you are concerned about damaging your tree, then you can also smash the aphids between your fingers where they are at their highest concentration. This is not recommended for the squeamish gardener like myself, but it is effective.

So, these pests that easily appear and easily multiply are easily controlled without the use of pesticides. For the optimistic, aphids are a good thing because shortly after their appearance, an army of beneficial insects will follow. Once these beneficials gorge themselves the next step, naturally is to reproduce. When their young hatch on a tree that no longer contains adequate food, they will seek out other pests in your garden, making your pest control efforts that much easier in the future.