Well! I Never Knew That!
By JENNY ARCHER
@bookbar (1609)
Sudbury, England
October 9, 2015 1:09pm CST
Walnut trees, along with other members of the Juglandaceae family (pecan, hickory), do produce a compound called juglone.
In a 2005 study, researchers did find that juglone induced death in human cells researchers applied it to, their conclusion,
" since juglone is present in human health and beauty products, a further understanding of its effects on human cells is warranted.”
These properties, too, are already folk knowledge. Lazy fishermen used to dump unripe walnut hulls into ponds to take advantage of juglone’s toxic effects; the stunned fish would float to the surface, easily collectible.
As a herbicide, juglone will be familiar to some gardeners as the reason you don’t grow certain vegetables too close to a black walnut tree, the richest source of juglone in the Juglandaceae family.....: it inhibits the respiration of certain plants (including tomatoes, potatoes, peppers, and eggplant) within the walnut’s root area, which in a mature tree can extend up to 80 feet.
Well I knew Rhododendrons did that, but someone's just given me a young Walnut...hope it's not Black !!
8 people like this
11 responses
Nothing like a sporting outlook, from an Asylum window!
@owlwings (43910)
• Cambridge, England
10 Oct 15
A good alternative to dynamite, I have found, is a mixture of sodium chlorate and sugar in a golden syrup tin suspended under a plank of wood with a Jetex fuse poked through a hole. It creates a spectacular fountain and results in stunned fish floating to the surface in a radius of about 20 yards up and down the river.
1 person likes this
@owlwings (43910)
• Cambridge, England
10 Oct 15
One very often finds a single walnut tree in an old orchard. Juglone is apparently highly toxic to many herbivore insects, so the effects of a walnut tree in an orchard would be to protect the trees from insect pests. Mind you, the walnut usually found in Britain is Juglans regia (native to the mountains of Central Asia), not Juglans nigra, which is native to North America, though nigra was introduced to Britain in the 1600's, so one might find Black Walnuts grown here.
The word 'walnut' means 'foreign nut' (as opposed to our native nuts, the hazel and cob). It takes a long time from planting to fruiting (about 12 years, I believe) and reputedly benefits from being beaten with sticks to gather the nuts - in common with dogs and women, so the old rhyme goes!
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@allknowing (136435)
• India
10 Oct 15
Walnuts do not grow where I live. Never knew there were black walnuts though.
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@TheHorse (218846)
• Walnut Creek, California
11 Oct 15
Walnuts do taste a bit bitter. Do they have to be baked before we eat them? I know Indians ate acorns, but they did something to the before eating them. Raw acorns might be good for squirrels, but I've heard they're bad for humans.
1 person likes this
@AbbyGreenhill (45494)
• United States
9 Oct 15
I bet those fish weren't safe to eat.
1 person likes this
@everloving (439)
• Chennai, India
9 Oct 15
Thanks for the information 
. I did not so far know that walnut has such effects.
. I did not so far know that walnut has such effects.1 person likes this
