Juglone persistence?

[Frogleg]

How long does juglone persist in the soil, and/or after trees are cut down? I expect the now-sunny area I want to plant tomatoes in is full of roots.

[Penelope Periwinkle]

I _think_ juglone is released by the roots as they rot.

Ah, here:

to this fact sheet, tomatoes are sensitive to juglone, so you might want to consider containers or raised beds there for a few years. Tilling it up and physically removing the larger roots would probably help, but I wouldn't want to risk losing plants there.

I understand wanting to use the space, I just had three large mulberry-less mulberry trees taken out on Thursday. The center of the triangle formed by the three trees is pretty barren. I don't think it's a toxin problem, more a competition problem; but I'm thinking I won't put anything but some sort of cover crop in that area for a couple of years. These mulberry-less mulberry trees sprout all along the roots, so I expect it will take a few years to really kill the blasted things.

On a brighter note, though, I think they were the major reservoir for the thrip plague. Around the first of June I could look up and see all the leaves on these massive trees curling up from thrip damage. I can't wait to see how my tomatoes do this year!

Penelope

[Frogleg]

removed." Hah! Big help. How *many* years, fellas? Trees came down after Isabel in Sept, '03 (well, Mr. I'll Be There Tomorrow was probably done by Dec). I note that the fact sheet mentions large concentration under canopy, which gives me a little wiggle room.

Not with *my* back!

Mulberries are forever! They seem to *thrive* on eradication attempts.

Thanks for the reference. I got my plants yesterday, and am *aching* to get them in the ground. Well, I still have a couple of Big Pots, and maybe can find alternative locations for a while. Thanks.

[simy1]

Frogleg,

besides the other remedies suggested in the Purdue paper, you may consider making the bed with compostables, injected with an appropriate mushroom spawn

The purpose is to see if juglone can be made to decay faster. Fungi have the strongest enzymes, and they happily break down even petroleum derivatives that might be polluting a given soil.

In general, organic matter will help by speeding the decay of matter that is already present, by providing needed nitrogen that is nearly absent in the roots (even fungi need it), by breeding a host of decay agents, and by improving the rate of mixing between topsoil and the lower layers.

Ask for a fungus that will go deep in the soil, not one that likes to live in dead wood (ink caps are one such species). Fungi have the strongest enzymes, and they might break down your juglone faster. You may also ask for plugs to inject directly in the largest exposed roots, or in the stump. The fungus will then propagate down the roots. You get the mushrooms once or twice a year of course.

Raised beds by themselves may be of limited help. A healthy tomato plant will go down four feet in light soil (light soil, the paper says, minimizes the juglone toxicity). On the other hand, if your soil is heavy, tomato roots might stop at a lower depth.

You could also put only tolerant veggies there the first year, and the tomatoes elsewhere. There are advantage in having separate gardening areas, and this is one.

[Loki]

Just what is juglones?

[Frogleg]

"Many members of the walnut family (Juglandaceae) produce in their tissues a chemical called Juglone. Production is highest in black walnut (Juglans nigra) and butternut (Juglans cinerea), with members of the genus Carya producing minimal amounts. Juglone is an allelopathic substance, meaning it affects the growth of other plants. Susceptible plants growing in close proximity to black walnut or butternut may suffer growth stunting, wilt ("walnut wilt") and death."

[GA Pinhead]

A substance produced by certain trees' roots that really inhibit growth. As I recall tomatoes are effected more than other plants. A defense against any competing plants.

John!

Loki wrote:

[Loki]

imagine. I did discover it wasn't good to wipe one's face with fresh walnut stained hands, unless one was fond of swollen eyelids.

Great wood too.