pests – Lee Reich

Posts

CLEAN APPLES, EDIBLE APPLES

March 13, 2024/5 Comments/in Fruit, Gardening/by Lee Reich

Popular Though They May Be . . .

Apples may be a common fruit, second worldwide and in the U.S., bested only by bananas, but they surely are not the easiest ones to grow. At least not over much of this country east of the Rocky Mountains, and here on my farmden. Throughout this area, insects and diseases are ready to pounce on virtually every unsuspecting apple tree.

Pesticides will control these pests but, if needed, are effective only if used rigorously: trees must be regularly and thoroughly doused with the correct material, used at the correct concentration, and applied at the correct times. No wonder the average gardener is daunted at the thought of growing apples!

Dwarf Liberty apple tree & Sammy

The prospects for backyard apples, organic apples, even in pest-prone regions brightened a few decades ago. Not all apple varieties are equally susceptible to diseases, and apple breeders went to work. Read more

Dry, Wet, Bad, Good?

December 26, 2018/10 Comments/in Fruit, Gardening, Pests, Soil, Vegetables/by Lee Reich

Some Bad

Wow! What a gardening year this has been. Looking back on 2018, it’s been the oddest year ever in terms of weather, insects, and disease.

After starting off the season parched, seemingly ready to go into drought, the weather in July did an about face. The rains began. Average precipitation here in the Northeast is about 4 inches per month. July ended up with about 6 inches, August saw 5 inches, September 8 inches(!), October 5 inches, and November 8 inches(!!).

All that rainfall brought humidity, which might have been responsible for my celeriac plants hardly growing, then rotting.

Celeriac, early in the growing season, before the rains

(Perhaps not, because this was my third growing season of failure with celeriac.) I’m taking this as a celeriac challenge. Perhaps next year I’ll try them in a large tub where I can have more control over soil composition and moisture.

The humidity also had too many figs morph into fuzzy, gray balls as they softened and sweetened.

Tomatoes this year tasted very good, as usual, but yield was way down and too many showed some rotting areas. (In my experience, growing tomatoes under variable soil and weather at various locations around the country, their flavor is mostly a matter of genetics; a good variety tastes good everywhere.) Particularly irking was anthracnose disease, which often isn’t noticeable when fruits are harvested, but quickly shows up as round, sunken areas.

Onions suffered this season. Mostly they were stunted, and I’m not sure why.

Zucchini was a bust because the plants petered out from powdery mildew and vine borers just after midsummer. I usually circumvent these common problems with multiple plantings, starting new zucchini plants in early summer to replace the decrepit ones. I forgot to replant this summer (probably because I don’t like zucchini all that much anyway).

Medlar is an uncommon, very old-fashioned fruit that I’ve grown for many years. Although it’s gotten a bad rap for it’s ugly — to some people — appearance, the flavor is delicious, the soft flesh creamy smooth like apple butter with a similar flavor livened with vinous overtones. Medlar fruit in hand Usually the plant is pest-free but a few years ago something, perhaps a fungus, perhaps an insect, started attacking it, leaving the flesh dry and crumbly. I have yet to identify the culprit so that appropriate action can be taken. Medlar pest damage

Some Good

Not that this past growing season was bad. I won the battle against soft scale insects (mealybugs) on my greenhouse figs, although their ecological niche was filled by just-as-bad armored scale insects. A close eye and an occasional spray of Neem oil kept flea beetles at bay from eggplants.

A couple of the same Neem sprays beginning in mid-September may have kept a new pest in the area, Allium leafminer (ALM, Phytomyza gymnostoma) at bay. Last year each of my near perfect-looking leeks revealed a rotted stalk as I lifted them out of the ground.

Allium leafminer

Then again, I did plant this past season’s leeks far from where the previous season’s leeks grew. Then again, the ALM flies can fly. Then again, maybe they weren’t here this year; perhaps the weather was not to their liking.

This past season’s leeks

There was also no sign this past season of the white flies that decimated my kale the previous season.

Spotted wing drosophila (SWD), a species of fruit fly that has invaded the country relatively recently, did mostly ruin autumn ripening yellow and black raspberries. But little damage was suffered by my favorite (and perennially most successful) fruit, blueberries, probably thanks to some experimental traps developed by Peter Jentsch of Cornell University.

SWD trap

Peppers were even more of a success than usual, mostly due to my staking the plants. The only fault of Sweet Italia, my favorite variety for its early ripening, for its flavor, and for its good yields, is that the fruit-laden plants flop over under their own weight. Eventually, the small bamboo stakes I used proved only partially adequate; next year they’ll get the stakes they deserve.

I treated a few beds in spring to a relatively new method for weed control: tarping. Laying a sunlight-blocking tarp down on the ground for a couple of weeks or more in spring warms the soil beneath, stimulating germination of any weed seeds lurking there. The sprouting seeds are disappointed by the incessant darkness. They die. Timing, temperature, sunlight, and duration of tarping all play a role in this techniques effectiveness.

(Tarping is very different from using black plastic mulches. The latter are kept in place all season long, with garden plants growing in holes or slits in the plastic. Soil beneath the plastic can suffer from lack of air or, if not drip irrigated, lack of water. Also, the tarp — mine came from www.billboardtarps.com — can be folded up and re-used for many seasons.)

And finally, we were happy to find some assassin bugs and anchor stink bugs, Stiretrus anchorago, in the garden. Both are beneficial insects — yes even that particular stink bug.

Immature beneficial stink bug

Good Overall

All in all, it was a good season — as always. The secret is to grow many different kinds of plants. No season, no matter what the weather or pests, has ever been bad for all plants.

Plagues Come & Go, With Some Help, and Seattle-time

August 1, 2014/10 Comments/in Fruit, Gardening, Pests/by Lee Reich

Meet me in St. L . . . Seattle

Come hear me lecture on August 10, 2014 on “Luscious Landscaping, with Fruiting Trees, Shrubs, and Vines” at 1 pm in the Garden Room at Magnuson Park. For more information, go to http://www.brownpapertickets.com/event/755459.

Plague again; keep calm

Every year it seems some new plague is ready to attack plants. A few years ago, late blight of tomato moved to the fore. Emerald ash borer, threatening ash trees, was first found on our shores in 2002. (Figuratively; literally, the insect, native to Asia, was first noted in Michigan.) What’s next?

Perhaps a calmer outlook is called for. A decade or so garlic mustard seemed ready to take over our world. Not so, now, perhaps because it’s being crowded out by Japanese stilt grass, which itself seems now ready to take over our world. Garlic mustard is native over much of the northern hemisphere, except North America, and was introduced here around 1860 as a culinary herb. As for stilt grass, it hitchhiked here from China about a century ago, as packing material for porcelain. It’s deer-resistant, for what that’s worth.

Plant problems come and go. The best approach is to keep calm and, in some cases, plant something different, something plague resistant.

Bean Beetle Management

Green beans are a mainstay of my garden, of just about every garden. More than 20 years ago, Mexican bean beetles (a species of ladybug!) found my bean plants and have plagued them every year since.

The adults, with eight black spots over a red or yellow background, wake up late from winter sleep to lay eggs on bean leaves. I’ve come to despise the yellow, balled up spiny larvae that gorge on leaves and other plant parts.

Still, I have managed to grow good crops of beans over the years, not by killing the beetles or their larvae, but by growing a different plant. Sort of. Rather than grow pole beans, which reside in the garden all season long to provide a constant source of beetle food, I have been planting successive crops of bush beans. Bush bean plants tend to bear quickly and for about 3 weeks, then peter out, so a new planting in a new bed goes into the ground every 3 weeks from mid-May until late July.

Yield from a planting tapers off just as its resident beetle population is beginning a feeding frenzy. Then it’s time to pull up the plants, thoroughly clear the bed of leaves and old pods, and rush it all to the compost pile. Chopping the debris with a machete and burying it beneath straw and manure, and watering the pile, as needed, sends the temperature soaring, killing most of the beetles. Bean beetles are good fliers, so cooking the beetles in the compost pile doesn’t solve the problem, just keeps it under control.

Death to the beetles, with restraint

Something strange happened this year: As of this writing, only one beetle larvae has been seen. Last year I doused the bean plants a few times with one of two organic sprays, which gave good beetle control. It also gave me the confidence to try growing pole beans, as I did in my pre-Mexican bean beetle days. They got some bean beetles but we did harvest pole beans.

The sprays were Entrust and Azamax, both approved for organic agriculture. The active ingredient in Entrust is spinosad, a compound found in bacteria, Saccharopolyspora spinosa, that was isolated from soil collected inside an old rum still in the Virgin Islands. Although toxic to a range of insects, it is otherwise relatively benign. Still, the label requires waiting at least 3 days to harvest after spraying.

Azamax is an extract of the seed of the tropical neem tree, native to the Indian subcontinent. In that part of the world, this one tree has been used as human food, insect repellant, bird repellant, and an ingredient of soap. It degrades rapidly in soil or in water, and is harmless to earthworms, honeybees, and insect predators. Food crops can be harvested right after spraying Azamax.

Still, Azamax and Entrust are pesticides. Perhaps the bean beetle cycle has been broken here and sprays can be forgone in the future. I’ll keep calm. No sprays this year, yet.

SWD, go away

The same two organic sprays might be called upon for another pest, the spotted wing drosophila, unaffectionately known as SWD. Also an Asian import, this one has moved east since being first spotted in 2008 in California. It is hard to keep calm with this pest because it attacks blueberries, my favorite and heretofore my most reliable and abundant fruit crop. The pest is also fond of blackberries, raspberries, and — not that it matters to you or me, because we don’t eat them — honeysuckle berries.

Again, there are management options. Because SWD seems to blow in from more southerly locations, a fine net could exclude them. Prompt refrigeration of harvested berries for 3 days kills larvae within. Thorough harvest of sound and unsound berries also keeps populations in check.

And then there’s Entrust and Azamax (or some other neem product), any of which I consider a last resort. I’m setting up traps to monitor if and when SWD arrives. (For information on monitoring, see http://www.fruit.cornell.edu/spottedwing/monitoring.html.) Till then, and after, I’ll try to remain calm. Om. Om. Ah-oh-om.