ROOT APHIDS: WHY THEY CAN BE THE GREATEST THREAT TO CANNABIS
NO PEST GUARANTEE• PORTLAND
If you have a cannabis grow room and suddenly notice your plants looking a bit off and undernourished, the first thing you would do is check for all the common quick fixes. So you make sure they’re adequately watered and receiving the right nutrients according to your feeding schedule. You’ll also ascertain that pH is in the ideal range and there are no visible signs of marijuana bugs in the stems and leaves of your plants. Finally, you take a look at the roots and your worst fear is confirmed—you have root aphid infestation.
Root aphids can be a pain in the neck for cannabis growers in the NW Oregon area. These pervasive and obnoxious pests destroy cannabis crops by sucking on the roots and leaving an enzyme that causes lesions that are not able to heal. As a result, nutrients from the roots are leached, leaves wilt, and overall plant growth is stunted.
In order to identify, treat and prevent a root aphid infestation, you must first get to know about them better.
WHAT ARE ROOT APHIDS?
Root aphids have been around for more than a century. They’re among the worst enemies of commercial crop growers, first decimating vineyards in France and almost destroying the wine industry in a scourge known as the Great French Wine Blight in the mid 1800s.
Root aphids belong to the phylloxera family of bugs and are native to the eastern and southeastern United States. First discovered in California in the 1850s, they found their way to French vineyards a decade later when American grapevines were exported to France to help fight powdery mildew. This led to two-thirds of the destruction of Vitis vinifera vineyards in Europe by 1900.
Part of what makes root aphids so prevalent is their prolific life cycle. As soil temperature rises in the spring, nymphs begin to feed on root sap and mature into adults in just two to three weeks. These spring and summer feeding adults are strictly females that can reproduce without male fertilization. A single female can produce 100-150 eggs over a period of six weeks and new nymphs invade other root areas to feed and cause gall formations. As they mature, they begin producing the next generation of eggs. The cycle goes on and between five to nine overlapping generations of root aphids can take place in a single growing season. Newly hatched nymphs in September and October usually hibernate for the winter.
With such a diverse and fertile reproductive cycle, it’s no wonder why both growers and hobbyists have such a difficult time eradicating these cannabis pests. Now let’s take a look at how to find out if root aphids are attacking your cannabis plants.
HOW TO SPOT ROOT APHIDS IN CANNABIS PLANTS
Now that you’re equipped with information about root aphids, you need to know the telltale signs of a root aphid infestation in your cannabis grow space.
It wouldn’t be wise to immediately dig up a plant to inspect its roots—that’s why it’s important to first rule out other possible causes that are making your plants look unhealthy.
Cannabis plants afflicted with root aphids will look undernourished and their growth will be stunted. If they’re flowering, the flowers will be smaller than usual. The leaves exhibit signs similar to iron and magnesium deficiencies, so they’ll turn yellow because the root aphids are sucking out these nutrients from the roots.
After you’ve ruled out other probable causes in plain sight, it’s time to get to the bottom of things—examining the roots. Cannabis roots that are afflicted with root aphids will turn yellow, swollen and hard. You’ll need to keep your guard up at this time because damaged plants will also become susceptible to other issues like root rot and fungus.
Root aphids are somewhat difficult to identify and often confused with other marijuana pests such as fungus gnats. These pear-shaped little nasties measure about 1 mm and range in color from white, yellow, orange, brown, and green. They have the ability to camouflage with particular roots they feed off, so in the case of cannabis you’ll find white, tan, brown or orange root aphids.
Root aphids begin to resemble fungus gnats when they start to grow wings. If you do get confused with the two, keep in mind that root aphids have shorter legs and are chunkier than the latter. Their wings are also longer and more slender. In contrast, fungus gnats have slimmer bodies, longer legs and rounder wings.
PREVENTING ROOT APHIDS IN CANNABIS GROW ROOMS
As the old saying goes, “Prevention is better than cure.” This is the ideal scenario if you operate a cannabis grow room because root aphids are so difficult to get rid of. So it’s best never to have them to begin with. Outdoor growers don’t have this advantage because root aphids could be thriving on plants along the perimeter of their grow space. But with an indoor grow room, you can apply extra measures to seal your grow space completely and keep it clean. Regular sterilization is vital since root aphids can lay their eggs in walls and remain dormant during the winter.
You can also be more stringent when sourcing out soil and grow medium so you can ensure you don’t get material that has been infected with root aphids. Make sure not to overwater your cannabis plants, too, as root aphids seem to love extra moist soil. And if you do bring in fresh, new clones, be sure to give them a good root drench first with organic insecticides. Furthermore, if you have pets around, make sure they don’t get into your grow room as they can be unknowing carriers of these pesky little suckers.
But what if you already suspect a root aphid infestation in your cannabis grow space? Well, it’s time you get in touch with an organic pest control expert like Ryan at ANT & GARDEN ORGANIC PEST CONTROL in Beaverton Oregon.
OREGON CANNABIS PEST CONTROL FOR ROOT APHIDS
For decades, I’ve helped homeowners and commercial growers in Oregon treat, eliminate and control marijuana pests and diseases in their homes and grow spaces. When it comes to root aphids on your cannabis grow, I highly recommend catching these pests early on so I can keep their populations down and even eradicate them without injuring plant roots beyond repair.
I begin with a root drench using a citric acid-based pesticide which is organic, safe and non-toxic to humans but highly effective against root aphids. Depending on your infestation, I may also decide to apply organic foliar applications as a preventive measure. Then, I will use any or a combination of the following:
This naturally occurring soil bacterium is placed in your water reservoir to help kill root aphids at the larva stage when watering your cannabis plants. BTI also kills mosquito larvae and fungus gnats without causing harm to food crops and your water supply.
This entomopathogenic fungus acts as a parasite which kills or seriously disables root aphids. It occurs naturally in soil and can be found in commercial pesticides like BotaniGuard® 22WP.
These naturally occurring microscopic roundworms found in soil are a non-toxic, safe prevention method for cannabis crops.
PARASITIC WASPS AND PREDATORY BEETLES
They’ll eat any root aphids living on the surface of your cannabis plants. I usually seal them with sand and landscaping fabric on your pots so they cannot escape.
AZADIRACHTIN EXTRACTS FROM NEEM SEEDS
This is another effective plant-based pesticide that has demonstrated impressive success in treating and preventing root aphids in cannabis.
ROSEMARY OIL AND LEMONGRASS OIL
Both oils are organic, plant-based pesticides that are effective when treating light cases of root aphids and preventing recurrence.