Rabbits, squirrels and chipmunks get all the glory as obnoxious pests, but truth is there are some smaller ones who are just as irksome to our vegetable seedlings. Can you identify what these early season pests these are?
|Leaf miner, typically an early-season pest, causes damage to early greens. It attacks plants in the family Chenopodiaceae which includes chard, beets, and spinach. (The right two pictures). Leaf miner is a fly larva that feeds on the leaf tissue, and burrows between the layers of a leaf eating everything but the epidermis. Early damage is a slender, winding, transparent ‘mine’, that later these expand and become larger blotches on the leaves. Inside the mine is a pale, white maggot. The fly overwinters as pupae in the soil and hatches in late April and May, and there are several generations per year. The adult fly then lays eggs on the leaves and the resulting larvae begin their damage.|
Ah! Now what?
Healthy plants and soil deter them from making a home on your plants, but that’s often not enough. If you’re super diligent, and love your leafy greens, you can look for clusters of oblong white eggs on the underside of leaves before you see the mines. Row covers prevent flying critters laying eggs on leaves, but might not be realistic for the few plants in your backyard. Since adult flies will emerge from soil near where infested crops or weeds were found the previous fall, rotating where you plant is helpful in preventing them longer term.
Most important is to clean up infested leaves: Remove all leaves infested by larvae as soon as you see them.
Flea beetles (left photo) are a group of small leaf beetles with large, powerful hind legs and can jump when they are disturbed. They overwinter in leaf litter and emerge in early spring. The adult beetles mate and lay eggs in the soil nearby and, when the eggs hatch, the developing larvae feed on plant roots and underground stems. After a short pupation, the beetles emerge from the soil as adults and begin feeding on nearby plants. They most enjoy plants in the families Solanaceae (potatoes, tomatoes, eggplant, peppers) and Brassicaceae (broccoli, kale, cabbage, collards).
Adult flea beetles feed on plant leaves and stems, and create shallow pits and holes in leaves that are roughly circular and at most 1/8 of an inch in diameter. Leaves that have suffered heavy feeding injury have a “shot hole,” on their foliage. Though damage often looks serious, it is often not as critical to plant health as it may appear, especially if the vegetable plants are well established.
Ah! Now what?
In addition to the general guidelines of building healthy soil and plants, there are numerous control and treatment options, depending on your style of gardening. Here is an excellent article that outlines many.
Eliot Coleman in Four Season Harvest, writes, “The gardener’s aim is not to protect sick plants but to enable healthy ones. You enable plants to attain their natural insusceptibility by removing plant stress. You remove plant stress by working to optimize all those factors involved in plant well-being.”
As I spray (or squish) the pests on my plants, I sometimes think about, and struggle with, the killing of creatures amidst notions of the divinity of ALL of G!d’s creatures.
Classic Rabbinic commentary says that one is permitted to kill an animal if it serves to support human life and purpose. This underlies both eating meat as well as ritual, sacrificial slaughter. Both physical and spiritual needs are acknowledged.
It is easy to argue that growing food is necessary for healthy humans, and anything that gets in the way of that goal is a hindrance and must go. I understand that on an intellectual level.
The lesson I choose to highlight is in the value of healthy ecosystems, and keeping a balance. It is about interconnectedness, nuance, responsibility and humility. I am not alone in my thoughts. Here is another woman’s journey towards accepting the value of the life of a mosquito.
There are many understandings of why G!d created humankind on the sixth day, just before Shabbat. One is that amidst home sapiens arrogance, it may be pointed out that even the gnat preceded humankind in the act of Creation. Humility indeed!
Another reasoning is that the first mitzvah (commandment) they were then able to fulfil was to overserve the Sabbat. (Sanhedrin 38a).