Pests – Page 8 – Lee Reich

GOOD FUNGI AND BAD INSECTS

August 21, 2014/8 Comments/in Gardening, Pests, Soil, Vegetables/by Lee Reich

Fungi I Like and Bean & Japanese Beetles (Don’t Like)

Where once scorned or appreciated only after being sautéed in butter, fungi have finally come into their own. If you’re among those who isn’t awed by fungi except when they’re sautéed, swallow this: each gram of soil (the weight of a paper clip) might house over a million fungi, or anywhere from 10 to 100 pounds of them in the top 6 inches of a 1000 square feet of soil. And most of what they do — for plants and soil, forget about your taste buds for now — is beneficial.

I recently heard of a project using fungi as a building material. On exhibit at the Metropolitan Museum of Art’s PS1 in New York City is Hy-Fi, a cylindrical tower built our of bricks made from fungi that have been fed cornstalks, the fungi’s fine, thread-like hyphae growing to create dense bricks. An organically grown building! Among the benefits touted were that a building made of fungi could be recycled.

I’m not so sure that a building that can be recycled is a good thing, but one statement by the architect did raise my hackles: that the building could be made of waste materials, such as cornstalks. The same argument could be or has been used for ethanol production, which could be made from the same waste material.

Corn stalks might be waste material in the sense that we don’t eat them, perhaps not even always feed them to animals. But corn stalks, wheat straw, and other so-called “waste materials,” as the architect perhaps inadvertently pointed out, are a gourmet delight for fungi. Also good food for bacteria (3 million to 500 million per gram of soil), actinomycetes (1 million to 20 million per gram of soil), as well as protozoa, nematodes, and other soil creatures. And don’t forget about earthworms (2 to 22 pounds per 1000 square feet of ground). There’s a lot of hungry creatures down there.

So these materials are not waste; they are food for soil life. They are what put the “organic” in organic gardening and farming. (They are “organic” in the sense that they were once living, and that they contain carbon compounds, mostly combined with hydrogen and oxygen.) They confer a range of physical, nutritional, and biological benefits to soil, plants, and, hence the animals, including humans, that feed on them. Depriving the soil of these organic materials is what led, in part, to the dust bowls of the 1930s.

Corn stalks as well as other organic materials too often considered as waste should be returned to the soil, either directly or after being first run through a compost pile. One measure of soil quality is the amount of organic material it contains.

Waiting Out Japanese Beetles

Japanese beetles have not come into their own; they have never been and continue to NOT be appreciated. The swarmed in a few weeks ago to make lace of the foliage of a whole host of plants. Grapes are among their favorites, evident by merely looking out on the landscape and picking out the hole-y grape leaves. (The leaf veins typically remain intact.) Although roses are also a reputed favorite, the beetles left mine unscathed.

Kiwi foliage made lacy by Japanese beetles

Japanese beetles made lacework of just this hardy kiwi’s foliage

Most interesting is the beetle’s effect on my hardy kiwifruits, specifically the super-hardy sorts (Actinidia kolomikta). I have four plants, 3 females — Krupnoplodnaya, Aromatanya, and Sentayabraskaya — and one male. Of all those plants, only the Sentayabraskaya plant was attractive to the Japanese beetles, dramatically so. Looking up, I can see sky through almost every leaf.

Japanese beetles are hard to keep in check. For a few plants, hand picking into a can of soapy water (the soap so they don’t just fly out after a quick bath) is effective. The biological insecticide milky spore disease, applied to lawns to kill the grub stage in the soil, is sometimes effective, especially in more southerly locations. Of course, beetles emerging from the soil in summer can fly, so milky spore is useless unless done on a neighborhood scale. Neem is a relatively benign repellant and insecticide that’s somewhat effective sometimes; it would require too much spraying, especially for something with such an iffy effect.

So I just wait the beetles out. Plants can tolerate a certain amount of damage and the beetles typically wave goodbye to go burrow into the soil and lay eggs sometime in August. The wait was especially short this year, with most of the beetles departing by the third week in July. Thank you guys, and gals.

And Where Did Mexican Bean Beetles Go?

A Mexican bean beetle threesome

Other pests also come and go. Mexican bean beetles, mentioned last week, still are keeping to themselves, wherever that might be but not in my garden. Tomato hornworms, which are large caterpillars with voracious
appetites, stripping leaves from tomato plants in the matter of hours, turned up in a friend’s garden. Fortunately, piggybacking those beetles were what looked like grains of rice. They’re actually cocoons of a braconid wasp, which will kill the hornworm. Leaving parasitized beetles alone lets the parasite live to attack more hornworms.

Rice-like granules attached to tomato hornworm are parasites

Parasite attacks tomato hornworm; winner: parasite.

Also worth ignoring are the pimples that have been appearing on leaves of many pin oaks. Those pimples — hemispheres about 1/2” across — are galls. Plant galls are abnormal growth made in response to an irritant such as a bacteria, a fungus, or, most commonly, an insect. A few galls here and there rarely do a plant harm.

Those oak leaf galls are pocking almost all the leaves on my pin oak. Still, I’ll ignore them or admire them; they sort of liven up the look of the tree. It’s too late, anyway, to do anything about them.

WEEDS, BIRDS, & PEST-FREE CURRANTS

August 15, 2014/0 Comments/in Fruit, Gardening, Pests/by Lee Reich

I Battle Weeds and Birds, but Currants are Care-free

Part of my weedless gardening technique (which I thoroughly fleshed out in my book Weedless Gardening) involves — sad to say, for some people — weeding. After all, no garden can ever be truly weedless. Even people who spray Roundup eventually get weeds as they inadvertently “breed” for Roundup-resistant weeds, which now exist. My techniques are weed-less rather than weedless.

Which brings me to hoeing. Most years my hoe rests on its designated hook in the garage. This year, it’s hardly made it back to garage, mostly just leaning up against the garden fence alongside the gate. “And why is this?” you might ask. The answer is rain. This season, rainfall has been dropping in sufficient amounts at regular intervals, all of which has coaxed good plant growth, including that of weeds.

More importantly, the rainfall has promoted plant growth in paths and between widely spaced plants. One leg of my 4-legged “weedless gardening” stool calls for drip irrigation, which pinpoints water near plants. In a normal year, or a dry year, there’s little moisture to spur on weed growth elsewhere. This year, rainfall has democratically spurred weed growth everywhere.

Hence the hoe. The best hoes to snuff out young weeds without unduly disturbing the ground are ones with thin, sharp blades that lie parallel to the ground. All that’s needed is to slide such hoes back and forth a quarter of an inch or so beneath the surface, cutting the stems of hopeful, young interlopers. The work, if can be called that, is quick and easy, not calling for the “iron back with a hinge in it” recommended for a gardener by Charles Dudley Warner in his 19th century classic My Summer in the Garden. Too many people use a pull or draw hoe, whose blade lies perpendicular to the handle, to try to conquer weeds.

The hoes I’m recommending are so-called push or thrust hoes. Some examples include the collinear hoe, the scuffle hoe, the stirrup hoe, and, my favorite, the wingèd weeder. With any of these hoes, roots aren’t damaged and lower depths of soil remain at lower depths so that inevitable weeds seeds buried there are not awakened as they are exposed to light. (Minimal soil disturbance is another leg of my 4-legged “weedless gardening” stool.)

Still, my wingèd weeder is not effective unless it is used — frequently this season, ideally once a week or within a couple of days after a rain. Used in a timely manner, the wingèd weeder does a quick, effective, and satisfying job.

Currants are an Old-Fashioned Fruit Easy to Grow

“The currant takes the same place among fruits that the mule occupies among draught animals—being modest in its demands as to feed, shelter, and care, yet doing good service,” wrote a nineteenth-century horticulturalist. Hoeing takes time, especially this year, so it’s nice to balance that with something — currants, in this case — that is “modest in its demands.”

One of my currant bushes, a Perfection (that’s the variety name) red currant, splays its stems upward and outward in an ornamental bed in front of my house. Sharing that bed, for beauty and for good eating, are huckleberries, lowbush blueberries, and lingonberries, and, for beauty alone, mountain laurels and dwarf rhododendrons.

The only care my currant gets is, anytime from November until late March, pruning. The plant bears best on 2- and 3-year-old stems so I cut away anything older than 3 years old and reduce the number of new, 1-year-old stems to the half dozen or so most vigorous ones. The whole bed gets a sprinkling of either soybean meal (1# per hundred square feet) or alfalfa meal (3# per hundred square feet) in late fall, topped with a mulch of leaves or wood chips.

The bush began bearing towards the end of June and a few clusters of the plump, jewel-like fruits still hang from the branches. Most people use red currant for jelly or sauce. I like to eat them straight up, with my morning cereal, for instance. The flavor is tart early on but has mellowed by now.

Currants were once a more popular fruit in America, and especially here in the Hudson Valley. They are one of the few fruits that tolerate shade (and deer!), and were often grown in the shade of large, old apple trees. Local folk, including children, would ride out to the orchards in hay wagons for communal picking.

Currant is, truly, among the uncommon fruits for every garden (good book title, that).

I Reluctantly Share Some Blueberries with Birds

Just a quick note about my blueberries, which are also relatively carefree. Last year’s abundance of cicadas may have upped bird populations, or at least made birds believe that lots of food would always be in the offing. Not so, birds. Perhaps, then, that’s why so many bird are fluttering all around my blueberries, mostly on the outside of the net that encloses my Blueberry Temple of 16 plants.

Right now a hawk — a cardboard one, swooping in breezes as it hangs from a string fixed to the end of an long, inclined bamboo pole — is meant to dissuade birds from even approaching the net. Calm mornings keep the hawk still enough so an occasional bird find their way through the net (where?) to venture into the Temple.

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.