The Tribune

By Gardener Jack

It takes a lot to be champion and the title holder of the world's worst weed in many people's opinion has all the qualities you look for in a really great weed: it is invasive, it stifles all opposition, it is close to impossible to get rid of. Ladies and gentlemen, I present Cyperus Rotundus, known in the Bahamas as nutgrass, and in other places as nut sedge or that bloody nuisance.

Nut grass above ground looks like clumps of very green grass. It is a sedge and is closely related to papyrus. One of its means of propagation is seedage, the seeds produced from a stalk that is triangular in cross section. If this were the only way it propagated it would be easy to control, but under the ground that tuft of grass- like greenery is attached by a thin thread to a nut-like tuber several inches away, which in turn is attached to another nut-like tuber, which in turn is attached to another, and so on.

When you pull up a tuft of nutgrass you leave those other tubers and they quickly send out growth to hit the surface. Pull up a dozen tufts of nutgrass and three dozen will replace them in a few weeks.

To become the world's worst weed needs more than endurance and longevity. The opposition must be overcome, so nutgrass is allelopathic: its roots send out substances that are harmful to all other plants. While other weeds smother opposition, nutgrass poisons opposition.

So how does one get rid of nutgrass? Texan Howard Garrett, the Dirt Doctor, has this advice on his website: "There is only one guaranteed, foolproof way to completely kill nutgrass. First, dig out every tiny piece of the plant including the seeds and nutlets. Make sure you sift the soil through a mesh screen. Dump the collected material on the driveway and burn it. Sweep up all the ashes and seal in a concrete box. Drive to the coast and dump the sealed box 20 miles offshore."

If this is too drastic for you I suggest you simply sell your home and buy another one without nutgrass in the garden.

I have seven small (dinner table size) vegetable plots in my garden and one of these is rife with nutgrass. I used the regular herbicides on sale locally but the nutgrass - like a true champion - did not blink.

In order to kill nutgrass a herbicide specifically designed for it had to be created. The herbicide kills nutgrass and nothing else that you are likely to have in your garden. My research led me to conclude that 'SedgeHammer' from the Gowan Company (formerly 'Manage' from Monsanto) was the product to use, but I could not find it locally. The instructions called for repeated applications a few weeks apart until the problem was solved.

My local nursery carries 'Image' by Ambrands, which kills nutgrass and just a few other weeds. Problem solved, you might think. But the price of a container is $60.35. I had to ask myself if it was worth over $60 to remove one type of weed from one garden plot. My wife and I have 16 grandchildren and I would rather spend the money on them than a weed killer.

So I have decided to carry on removing nutgrass whenever it appears, taking out as many 'nuts' as I can at the same time. Over time many weeds can be controlled by attrition. If you mow an area with shepherd needle, say, you will not kill the weed. Allow it to grow to the flowering stage and mow it again and you have depleted the plant. Repeat the mowing without allowing the shepherd needle to seed and it will eventually die out.

It is possible that solarisation of the soil using clear plastic sheeting during the hottest months of the year might do the job. I'll certainly give it a try. These days, $60 is a lot of money.

gardenerjack@coralwave.com