Farm Friday, July 1st, 2022
Full-on summer
These are the days of long hours of daylight and an endless list of projects for the garden. It has been hot. Minnesota Public Radio was saying yesterday that it was the 11th hottest June on record, and I believe it.
Despite having a couple little rains, we have been busy watering the thirsty crops. We are lucky that our soil is mostly a fine silty loam, which holds moisture very well. Even so, our potatoes definitely require additional water this time of year.
Speaking of potatoes, this week has been a big week for potato beetle remediation. The Colorado Potato Beetle survives the winter in the soil and then emerges in the spring to seek out mates and find potato plants. Since we grow potatoes every year, they are there waiting for us in the early summer, when the first sprouts emerge from the soil. The adult females lay eggs on potato leaves and then the larva hatch and proceed to eat to their hearts’ content. Then, when the larvae reach maturity, they go down into the soil and become adults. The first generation of the larva can do serious damage to a potato crop. But the second and third generations, if unchecked, can devastate a farm. I have had years when I let the potato beetles go nuts, and I regretted it. When they skeletonized the whole potato field, they moved on to the tomatoes, eggplant, and peppers. On a farm tour, my friend said it “was like a horror movie.”
Organic control of potato beetles has been an evolving process. When I first started farming, there was a bacteria (Bt var. San Diego) that you could spray on the leaves. When the young larva ate the bacteria-laden leaves, they would get sick and die. This was a problematic solution because it did not kill the big larva, nor the adults, nor the egg masses. So, the timing was essential, and you had to spray weekly to keep up. And a rain storm could wash it off. Then the GMO companies engineered Bt into the genes of transgenic potatoes (documented studies on health effects with rats led Mcdonald's to require their french fries to not have Bt potatoes). Since then, Bt var San Diego hasn’t been available to farmers. I don’t know if there is a connection.
Later, an organism called a “spinosad” was converted into a powder or liquid that could be mixed into water to spray on potato beetles. I used the spinosad for years. I called it the “spine-so-sad” because it worked like a conventional pesticide. It killed on contact, so it killed adults, big larvae, little larvae, and egg masses. It also killed every other insect it touched. It was a massive convenience because I only had to spray the potatoes twice in a whole season. It felt like cheating. A problem was that anything that is that lethal creates an instant evolutionary selection pressure on the beetles. And that is what happened. Five years ago we started to see beetles surviving the spinosad spray. The good life was over.
Three years ago I purchased a couple of different natural insecticide sprays to try. I wanted to alternate using one, then the other, in order to slow down resistance build-up. Neither spray worked as well as Bt or the spinosad, but they did slow down the infestation somewhat, I think.
Last year, we tried a non-chemical intervention. We sent children out to the field as “potato protectors.” They each had a plastic water bottle filled with soapy water, and they would collect the adults and big larvae and put them in the soapy water. Every time a family would visit, I would send them out to the potato patch. My goal was to stop the first generation, and it worked! So this year, we tried the same thing with our students last week. Less success. So this week, Ben and I spent four hours scouting the potato patch and removing the beetles. I think if we do it again next week, we will have slowed the first generation down enough to avoid the horror movie scenario.
In the midst of the hot weather, we have been spending some quality time in the hoophouse, tying up the tomatoes. It takes an hour to do one row. We try to avoid the hottest part of the day, but you also don’t want to go touching tomatoes when they are wet with dew - that might transfer disease from one plant to another. So mid-morning, with a podcast or conversation.
The chickens and guineas have finally been let out of the bird-flu quarantine that they were under. I think that started in April, so they were ready to be free-roam chickens and guineas again!
Precious, our llama, is doing well. This week, when we stand her up, she has started to take herself for walks around the barn. We walk with her and make sure she doesn’t run into anything dangerous, because she is a little unsteady.
In writing news, I published an essay about Morris dancing and it was picked up by a group in England called “Tradfolk.” Here is the link to that essay.
