Post Punk Kitchen Forum

And I have a gigantic black walnut tree in my yard. The only tree back there, actually. So of course the tree sheds in the winter all over and the nuts fall all over everything in the summer. A chemical compound called juglone is the culprit and the long and short of it is there ain't nothing I can really do about it. The compound is really strong in the roots as well. So, I guess my garden is forked.

And yet...everything is growing pretty well. The tomatoes are right beside the tree and they seem fine so far. Any thoughts?

I have heard this too, but I say keep doing whatever you have been. I am assuming the tree has been there for a bit already, so the toxins would be in the soil and if things are growing, yay for you!

Whoa! Really..??My neighbor has one, and I've never had any problems.

A really big hairnet under the tree and raised flowerbeds with fresh topsoil next year?

Isa, I'm reading up on this right now. I say, if your plants are thriving don't sweat it.

Like a lunchlady?

Exactly. You could start a neighbourhood trend, and a side business making walnut tree nets.. NutNets! I get a 15% cut for thinking up the idea, you do the rest of the work, nice doing business with you k.

First, are you certain it is a Black Walnut? There are other trees that look similar.

Second, some plants are more tolerant to juglone than others. There are many black walnuts growing along the edge of my yard, but the mulberries, hackberries, and black raspberries are not bothered by them.

Allelopathy!

There are plants that do better than others. But yeah, rake and pack out the leaves and walnut husks.

You can eat the walnuts though! And use the fleshy husks to dye things brown!
http://www.ces.ncsu.edu/fletcher/staff/ ... nions.html

http://pubs.ext.vt.edu/430/430-021/430-021.html

ps- I talk about this in my ranger campfire talk! Juglone!

They're also really toxic to horses, and used to prevent/treat parasites in humans...wooo facts

Okay, I've been doing some readin' and stuff. Here's a little ditty from our pals at Cornell:
http://csip.cornell.edu/Projects/CEIRP/ ... opathy.htm

I had NO IDEA that sunflowers were alleopathic to tomatoes! Look under "selecting a cover crop" under this article:
http://www.gardening.cornell.edu/factsh ... plant.html

OH, yay. I have Tree of Heaven too. I have been trying to eradicate it, with mixed success. Well, that and the honeysuckles. Sigh.

Sunflowers are also bioaccumulators of lead and radiation, so...uhm..there's that.

Tree of Heaven pretty much requires herbicide...and even then its mixed success. That thing root suckers like noone's business. It might actually be a better candidate for "hack and squirt" which is a slower death by herbicide method.

When it comes to invasive plants, I'm not at all organic. Well, somethings hand pull well.

Sunflowers-I just don't understand how a plant's flowers can be so beautiful, the seeds so tasty, but the roots are such jerks! How does that even work?

Juggalone.

I thought it was actually the seed husks that are allelopathic? Unless its both the roots and seed husks.

According to the Cornell stuff it is the roots as well.

My sister has two or three of these in her backyard. They pick up at least a 5-gallon bucket full every few days. Besides being toxic (which I didn't know before), they smell AWFUL in the spring if you let them rot in the lawn over the winter.

I wish I had a walnut tree... yummy!! My grandma's sister used to send me walnuts every year until she passed away. I'm not sure I ever met her (I don't remember meeting her so maybe when I was really young I did) but she heard that I'm one of the few in the family that likes nuts so I'd get a large ziplock bag or two each year of *shelled* walnuts and a smaller bag of black walnuts! So good.

Not exactly sure the best way to tackle this, but...as far as plants being allelopathic, many early successional, old-field type species grow fast and take up whatever sunlight they can get. Sunflowers probably fall into this group because they grow rather tall in short order. Usually those species do not invest so many resources into chemical competition because they are annuals. Their seeds are dispersed and take hold where ever there is plenty of light. Over time, the old field is taken over by taller, longer lived species which by the nature of their longer lifespan they have to be better competitors to keep their foothold. The competition can take multiple forms (growing very slowly in the understory and shooting up when a gap develops is one) including allelopathy. On the other hand, some plants have evolved to share resources with others of their own species and also with fungi. It's a crazy world and Mother Nature is always encouraging different strategies!

My guess is that sunflowers, which have heavy seeds, may have developed allelopathy to protect offspring that are dispersed near them.