Sunday, August 14, 2016

Ants


Weather: We’ve gotten some rain this week, but have had more winds, thunder and lightening that led to nothing; last rain 8/13.

What’s blooming in the area: Hybrid roses, buddleia, Russian sage, trumpet creeper, silver lace vine, rose of Sharon, David and purple garden phlox, zinnia, Sensation cosmos. Apples began showing color.

Beyond the walls and fences: Buffalo gourd, scarlet bee blossom, yellow evening primrose, velvet weed, bindweed, green leaf five eyes, yellow purslane, goat’s heads, alfalfa, Queen Anne’s lace, Hopi tea, horseweed, golden hairy asters, goldenrod. Quack grass was up everywhere; goat’s heads and Russian thistles were beginning to emerge.

In my yard: Caryopteris, garlic chives, large leafed soapwort, leadplant, larkspur, sea lavender, blue flax, catmints, calamintha, perennial four o’clock, hollyhocks, sidalcea, winecup mallow, pink evening primrose, white spurge, Mönch asters, purple and cutleaf coneflowers, Mexican hats, chocolate flowers, coreopsis, blanket flower.

Bedding plants: Wax begonias, snapdragons, sweet alyssum, French marigolds, gazania.

Inside: Zonal geraniums.

Animal sightings: Rabbit, hummingbirds and other small birds, geckoes, bumble and small bees, hornets, ants. Grasshoppers continued to denude apple trees and more tent nests appeared in trees of all types in the village. Crickets have been loud at night.


Weekly update: I have a problem with ants. During the summer I have up to six hills of large black ones who deliberately bite. I also see them stealing the grass seeds needed to maintain a prairie ecosystem already struggling with drought and high heat. In addition I have more than a hundred hills in my driveway gravel inhabited by smaller ants who leave me alone, but who turn my hoses, block paths, and brick borders into highways.

Generally, I’ve ignored the one to try to eliminate the other. The first time I was bitten, the swelling and itch didn’t go away for several days. It’s not the kind of problem you can take to urgent care, so I tried the various itch and bite ointments in the house. None worked. For some other reason, I took an aspirin, and the pain disappeared within half an hour. I happen to have a very low tolerance for aspirin, and keep it only for serious emergencies. Ant bites should not be that emergency that may trigger serious stomach problems.


The answer isn’t buying the magic potion, which probably does not exist, but eliminating the underlying problem. Controlling the ants.

I’ve tried whatever was available in the local stores. A few years ago some powders containing permethrin stopped their activity for about three weeks. That product no longer is available, and the replacements don’t even shut down hills for a couple days. Often when I’m in the store someone in the line will ask if what I’m buying works. I tell them no, it’s only temporary. They say they haven’t found anything either.

Efficacy seems a simple enough requirement for a commercial product controlled by the EPA, especially when the poisons pose potential dangers to me and the environment. But no, all that’s offered is risk and cost.


In frustration, I went on-line. Bayer told me there were many types of ants, and each behaved differently. It said, if I wanted to control my insects, I first needed to identify them. I paged through their pamphlet and found the little ones were pavement ants. The larger ones were not included.

I finally learned the big ones were harvester ants. They come in several colors and species, and seem to be primarily limited to the southwest. Too regional to interest a big international corporation like Bayer, whose financial experts are dedicated to maximizing their resources.

Armed with that information I looked more carefully at the available pesticides. They target fire ants, carpenter ants, Argentinian ants. Not the common pavement ants and not the vicious harvester ants. Even though they can denude grazing lands, they are not a serious enough economic hazard to justify the costs of research to develop new pesticides.

Deterrence isn’t the same thing as eradication. For that, the experts say I need to destroy the queen.

Does that mean I have more than a hundred queens in my drive, and that I have to take serious action against each one? Or, are the hills like crack motels, with several outlets for a single source?

I wanted a simple answer to that questions, but all I found on-line were rehashes of what I learned in elementary school, when I first heard about ant farms. You could recite it yourself: there’s a caste system with female workers who farm aphids. The writers never specify which type of ant they’re talking about. Apparently the farms are Texas red harvester ants.


I didn’t want to burrow through scientific articles, in a new field, but had little choice. I did finally learn from Noa Pinter-Wollman’s team that black harvester ant colonies in California can have up to six unique sites, and moved eight times in six months. Which one houses the queen?

I also learned the generic fertile ants fly from their nests to set up new colonies. Somehow that piece of information makes eradication an impossibility, since my neighbors have either given up controlling them or never tried.

I settled again on shutting down hills temporarily. When I started in the spring, the pavement ants had recognizable low mounds made of red sand. Within days, new holes appeared a few inches away. They apparently moved their entrance just beyond the treated area. The second hills were often less conspicuous. By the third treatment, they were often nothing more than holes in rocks, sometimes camouflaged by whatever weed was growing nearby.


The harvester ants began with the characteristic large crater of coarse gravel. Since then, they have settled for holes in the gravel, often two or three in one area.

Since hills disappear in winter, I assumed their life cycle was like plants. Nothing in those generic descriptions connects the life cycle to the calendar. I was forced to observe something that only interested me for negative reasons.

The pavement ants were back in mid-March this year, and the first harvester hill appeared in mid-May. Then they seemed to multiply in summer. I saw a bunch of new red sand-topped hills August 4, the day after our heaviest rain. A red harvester ant hill appeared August 6.

When I reread some of the Wikipedia articles I discovered those first hills were last year’s colonies, and the mid-summer ones are from new queens who don’t emerge until the summer rains. They’re more like biennials than annuals.

There’s no point in treating anything right now. Rain washes away or congeals powders, just as the ants are multiplying. But soon, I’ll go out again, with whatever I can buy, and renew the Sisyphean task unaided by any of the experts who are paid to help. Their corporate employers are secure in the knowledge their monopolies give me no choice but to buy their marginally useful products, or get bitten.


Notes:
Pinter-Wollman, Noa, Deborah M. Gordon, and Susan Holmes. "Nest Site and Weather Affect the Personality of Harvester Ant Colonies," Behavioral Ecology 23:1022-1029:2012.

Wikipedia entries on "Ant" and "Harvester Ant."

Photographs:
1. Mönch asters with sun through their petals after yesterday’s brief rain, 13 August 2016.

2. Treated ant hills in drive area with few hills, 31 July 2016.

3. Black harvester ant and its hole in the gravel, 6 August 2016.

4. Ant powder congealed in the rain; pavement ants crawl over it unharmed, 26 July 2016. This is the product being sold this year.

5. Red ant hill opened after the rains began, 6 August 2016.

6. Pavement ant hole hidden by stones, sticks and Siberian pea pods, 26 July 2016.

7. Raised ant hill in area of #1 after the rains began, 6 August 2016; they look like pavement ants despite the different architecture of the hills.

No comments: