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Dealing with Las Vegas insect invasion

Q: I took your advice and am treating pill bugs in my garden like slugs. I have drowned them with beer but they keep coming back. My neighbor is giving me his old cans of beer. I had to dig up the rhubarb plants and put them in pots. This is sure a frustrating year.

A: I am sorry to hear you’re having such a problem with pill bugs, sow bugs or roly-polies. Maybe I can add my two cents.

These critters are crustaceans, in the same classification as lobsters and crayfish. Some people have actually tried to eat them, probably thinking they should taste like lobster. They do not, so don’€™t even go there!

Roly-polies have gills and so must have a wet environment to stay alive. Anything in the garden that keeps moisture on the surface of the soil and around plants is going to encourage them and that’€™s where they’€™re going to be active.

Likewise, they will want to hide during the daytime underthings that collect moisture such as mulches, newspaper or boards laid on the soil surface, etc.

You can use this information to your advantage. Sometimes just laying these items on the soil surface and removing them during the day, followed by some light vacuuming with a cordless vacuum, can provide some cleanup.

As far as chemicals are concerned, I see diatomaceous earth recommended a lot. The problem with this recommendation is that DE cannot handle wet environments. These critters need wet environments so this recommendation is mutually exclusive of each other. Nice idea, but it has limited application.

As far as pesticides go, natural products containing pyrethrum are supposed to work. Heavier duty insecticides such as the synthetic pyrethrins, which (these end with-thrin in the ingredients) should also work.

I saw a report that the insecticide Sevin (carbaryl) also works. Be careful with this insecticide and apply it only at dusk or very early in the morning when bees are not present. It will leave a toxic residue on plants for several days. I hope this gives you some other options.

Q: I’m starting to see stinkbugs or squash bugs on a few squash leaves as well as the eggs on the undersides of the leaves. This year I bought some praying mantis eggs. I am now finding baby mantis in my front and backyard and on the very same plants the squash bugs are hitting. Do I spray for the bugs or hope the praying mantis will feast on the squash bug buffet?

A: That’€™s a really good question and it is one of the major difficulties we face when we try to manage our garden and fruit trees organically or as organically as possible.

You have introduced an insect predator into your garden to help keep some of the “bad bugs” under control rather than use pesticides. It is one of the cornerstones of integrated pest management or IPM.

We should also be realistic about what praying mantis can and cannot do. They are not focused on “bad guys” to help you. They are just looking for a meal. Their meals include “good bugs” and “bad bugs.”

This idea works great with some pesticides approved for organic production and it does not work well for others. For instance, if we use a pesticide allowed in organic production that targets a certain pest while not harming others it can work fine.

An example is using Bt insecticide that kills only the larva or worms of moths and butterflies. This insecticide will not harm mantids.

However, if we are realistic, Bt also kills the larva of butterflies which are not plant pests for our gardens such as the Monarch butterfly.

If we use insecticidal soap, which is also recommended in organic production, and apply it to our vegetables or fruit trees, we apply it is an “indiscriminate killer;” it kills any insect on contact whether they are squash bugs, leaf-footed plant bugs, aphids, honeybees or praying mantis.

When we choose to use “indiscriminate killers” but want to keep beneficials, like praying mantis, from getting harmed, then we must direct the spray on insects we want to kill and avoid spraying ones we do not want to harm.

This requires a lot of plant inspection on your part, which means looking for, identifying and targeting “bad bugs” with the spray.

Focusing on the use of beneficial insects for controlling “bad bugs” limits the use of pesticides. You must either not use pesticides, select pesticides that will not harm the beneficial insects or direct any pesticide sprays so that they come in contact only with “bad bugs.”

Another approach is to use “€œorganic”€ indiscriminate killers, such as insecticidal soaps, to keep bad insects under control. Realize you will have “collateral damage,” which occurs is the killing of good bugs and bad bugs with the hope that the good bugs recover after the spraying is over.

They will because sprays such as insecticidal soaps leave no toxic residue behind. This may not be true when using Dawn or Ivory Liquid when substituting for insecticidal soap.

Also, select “organic” pesticides that do as little damage to the general insect population as possible. This type of spray program limits the use of beneficial insects for any long-term control. It is really a “spray and pray” program.

Enjoy your praying mantids. They will migrate to other parts of your landscape as well as your neighbor’s area. Visit and inspect your garden and fruit trees often. Use plant sprays when “bad bugs” get out of control and target your sprays and direct them toward “bad bugs.”

Q: About 1½ years ago, I planted a package of leek seeds. They grew, but not very fast. I went on vacation and came back to leeks that were going to seed and looked more like garlic than leeks. They seem to have lots of “sets” at the base of the plants. Are they still good to eat? Can I pull them up and use the sets in the fall to plant more leeks? Can I freeze them? It’s been an interesting ride.

A: Leeks are grown from seed almost the same way as onions. You can harvest and use them any time. That will not be a problem. The problem is that leeks are best harvested and used when they are young and tender. They are more mild-flavored when blanched.

Leeks are biennials, just like onions. This means they bulb up the first season and, if left in the ground, send up a flower stalk the second season and produce seed. To do this they need two ’€œwinters’€ or cold periods. It sounds like they went through two cold periods, sent up a flower stalk and went to seed. Yes, you can plant the ’€œsets.”

Let’€™s cover how to grow them. Plant seed in the mid- to late fall, usually about mid-October or early November. You will transplant very immature plants to a new location in the spring about the first week of March.

Plant seeds one inch apart and about one-half inch deep. That is textbook but I broadcast the seed in a small area and cover the seed with a shallow layer of soil. I have planted them this way in containers as well. Over-winter these densely planted seedlings until they are lifted and moved in the spring.

In the spring, about mid-February to early March when they are at least six inches tall, dig them up carefully with a trowel or garden spade and separate them. Replant them in rows or blocks about four to six inches apart. Leeks can be fairly large so put the rows about 18 inches apart.

When they have put on some significant growth after transplanting you can blanch the base of the plant (turn them white) by not letting sunlight reach the bases.

Some people pile dirt around them while others cover the leeks with cardboard that prevents light from reaching the bases. Blanching is more for aesthetic and traditional appeal and some, including myself, say it is milder in flavor when blanched.

Fertilize them once a month during their growth period. They are shallow rooted so they will enjoy a surface mulch and frequent watering.

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