Four-Stresses to Kill a Weed

It’s probably 25 years ago that I sat in class and heard the general rule “It takes four stresses to kill a weed.”  By that I figure it takes four stresses to kill any plant – and I’m looking at my little alfalfa seedlings with a lot of sympathy.  They have experienced moisture stress.  I would think they have experienced heat stress – but there are heat tolerant varieties of alfalfa, and I was selecting for salt and water tolerance.  My alfalfa seedlings may still have a chance – I mowed the field high, to add one more stress to the weed competition.  I figure being cut down is at least one stress, and the alfalfa seedlings are much shorter, so they weren’t cut.

As I see knapweed bursting into bloom, I grab hold and pull.  In my pale, high clay soil, so much moisture has been pulled that at least half the plants come up with 3 to 4 inches of root – the soil is so dry that it isn’t holding the roots firmly.  I think pulling them up by the roots adds at least one stressor, just like a little herbicide adds a stressor.  Folks at the county weed department have spent a good portion of the 21st century adding insects that feed on knapweed – adding one more stressor.  It’s getting late now, but a little herbicide might go a long way with the other stresses.

Knapweed, flowering

Ox-eye daisy is classified as a noxious weed.  Since it has shallow roots, it is easy to control . . . which means it is easy to stress.  It’s persistence strategy is lots and lots of seeds – but one of the easy controls is healthy grass stands.  If the grass is thick enough, the daisy can’t get much of a start.  Grass makes better use of the soil nutrients.  Laird Byers used to call it a “poverty weed” occurring most frequently where fertilizers weren’t used.  The fertilizer strengthened the grass, and a little 2,4-D stressed the daisy a little more.  Along with this year’s drought, and a bit of mowing, the poor Daisy is likely to have three or four stresses in hayfields before a mild herbicide application. 

Canada thistle – like the daisy – produces lots of seeds.  Like knapweed, it has deep roots.  Still, a bit of 2,4-D works – it causes the cells that carry water and nutrients to grow non-stop.  It’s been around since the forties, and is a fairly gentle herbicide – though it got a bad rap in Viet Nam where it was mixed with 2,4,5-T in a compound called agent orange.  The problem was the dioxin in the 2,4,5-T.  The herbicide keeps the roots from coming back the next year.  We also have bugs adding to the thistle’s stress.


Thoughts of Old Friends

One of the spots where I was extremely lucky was an early career as a technician of varying varieties with the Soil Conservation Service, based out of the old bank building in Eureka.  During 6 years, beginning in the mid-seventies, I had the privilege of meeting and working with a lot of the older residents of the area.  Most had farms and ranches – one, Victoria Baney, was the landlord.

I returned from a week of snow surveys, and she confronted me at 08:00, with the statement, “Mike, I have a bone to pick with you.  Why didn’t you tell me that the girls in the apartment upstairs were running a brothel?”

Well, this was the first I had heard of it, so I actually came up with the correct response: “I didn’t know.  I guess we’ve been working different shifts.”  It was the right answer.  She was over her disappointment with me and laughing.

Laird Byers ran the county weed spray truck, and had a bad hip.  He had one of the first hip replacement surgeries, and later parked the truck in front of the building to show me a new piece of equipment.  Another resident saw the truck, and stopped to say something about weed control, but started with the comment, “What happened to the old crippled guy who used to run the truck?  Old as he was, he’s probably dead now.”  Laird couldn’t recover from his laughter – I had to explain the answer.  We never did learn the question that motivated the stop.

The state had mandated training and testing for herbicide applicators, so I offered the office for that purpose.  After the training session, Tom and Emmett Quirk caught me, explaining the last time either had taken a test was long before I had been born.  I rigged an overflow testing area in the backroom – neither had any problem with the test, didn’t need the college kid they kept in reserve, but obviously the last preceding exam was memorable.  I hadn’t realized how requiring a card to purchase specific herbicides could affect competent people over 70 – it probably had been over half a century since either had to sit for an examination.

I got a small grant and we tested an ultrasound generator to see if it would convince Columbia Ground Squirrels to relocate.  It didn’t.  I checked the device and some helpful neighbor had stacked 7 dead gophers around it – each killed by a 22.  Art Nutter asked if he could borrow the device to see if it would move a skunk out of his barn.  He had a certain level of success – it left the barn, but found a way to move under the kitchen.  On hearing this story, Victoria Baney had an idea – there were bats in the attic of the building.  We moved the machine into the attic on a Friday afternoon.  On Tuesday, Mrs. Bolen came by: “Mike, do you know anything about bats?  This weekend a whole bunch of them were getting into my attic.”  I admitted my ignorance on bats, removed the device, and this is the first time I’ve told the story.

And there is always the lesson from Chet Apeland, who chaired the conservation district board: “Mike, you really don’t want to get into an argument with an idiot.  After three exchanges, nobody can tell which one is the idiot.”