Hello Charming friends!
With the weather we’ve been having, cooler and TONS of rain, I’ve been noticing a familiar insect in my garden. It looks like this…
I bet, if you looked closely in your garden, you might see this pattern on some of your plant leaves. Kinda of looks like a mini race track, doesn’t it?
Well what the heck is it? Its leafminer, which are the larval (maggot) stage of an insect family that feeds between the upper and lower surfaces of leaves. If you want to watch a cool video on how the insect invests the leaf watch this video…
If for some reason the video doesn’t work click here.
Start watching at 25 second to about 1.10..I don’t agree with his treatment since he uses chemicals..but that decision is up to you!
Host plants include beans, blackberries, cabbage, lettuce, peppers, spinach, holly hock, zinnias, hydrangea etc. and a variety of ornamental flowers, trees and shrubs, or just about everything. On heavily infested plants it is not uncommon to find 6 or more maggots per leaf. Although damage can restrict plant growth healthy plants can tolerate considerable injury.
NOTE: if you have these on your vegetables leaves….do NOT eat them, eeeekkkkk!
Larvae are worm-like maggots (1/3 inch) which are often pale yellow or green in color. They create winding tunnels that are clear, except for the trail of black fecal material (frass) left behind as they feed.
Leafminer on my Zinnia Leaf
Mature larvae overwinter in the soil under host plants. As temperatures warm in the spring larvae pass to the pupal stage and appear as young adults in late April. Mated females use their needle-like ovipositor to lay up to 250 eggs just under the surface of the leaf epidermis. Within 10 days hatching larvae tunnel through the mid-leaf tissue, feeding as they go and leaving tell-tale wavy lines that are visible on the surface and eventually drop to the soil. Once on the ground, they dig 1-2 inches into the soil and pupate. Adults emerge within 15 days as adult flies. There are several generations per year.
Leafminer on Hollyhock leaf
Various types of leafminers attack various kinds of plants. They can be found on broadleaf trees, including elm, aspen, hawthorn, and poplar as well as shrubs and bushes, including lilacs. Damage can be limited in initial stages of infestations, but will increase as leafminer multiply. Even minor infestations, while not killing a plant, will cripple its hardiness.
Leafminers, in home gardens is a major cause of poor harvests because they weaken individual vegetable plants. They’re especially fond of spinach leaves and their tunneling severely decreases the attractiveness and value of the crop.
Leafminer on Hydrangea leaf
Natural, and organic control methods work best when fighting leafminer problems because they don’t harm the naturally occurring beneficial insect populations that largely keep the leafminer and other harmful pests under control. Pesticides can encourage leafminer outbreaks, natural controls and beneficial insects prevent as well as cure these pest problems.
Quick action, and not waiting until you spot leafminer tunnels in your plants’ leaves, especially if you’ve had problems with them in the past. Be prepared with the products you’ll need to prevent and destroy infestations. Then stay vigilant.
Things to do/use:
- Monitor plant leaves closely. At the first sign of tunneling, squeeze the leaf at the tunnel between two fingers to crush any larvae. Done soon enough, this killing larvae can allow plants to survive minor outbreaks. Pick off and destroy badly infested leaves in small gardens.
- The more healthy the plant, the less chance that leafminers will hurt it. Maintain plant health with organic fertilizers and proper watering to allow plants to outgrow and tolerate pest damage. Keep your soil alive by using compost and other soil amendments.
- Use yellow sticky tape to catch egg laying adults.
- Organic neem oil will break the pests’ life-cycle by preventing larva from reaching maturity. Neem oil may also have repellent qualities and interfere with egg laying activities.
- Botanical insecticides can be used to knock down adult insects but have little effect on the protected larval stage feeding inside the leaf.
Note: I receive no reimbursement for the products, just ones I’ve used and where to buy them.
Head out to your gardens and pinch off the leaves with this look on it..squeeze the leaf the toss in the garbage can or burn it!
I hope with this information, you are taking steps to becoming the best gardener for your plant children!