I thought black walnut, but the fruit is pear-shaped and a maple tree is growing quite close by. I thought maples and many others couldn't grow within a 40 ft radius from a black walnut tree. I'm not sure why, but I read that somewhere. Maybe the rule doesn't apply to maple trees?? Also, the fruit has a fuzz and is sticky. When it is cut open, it has what looks like a peach pit in the center. After touching it my mother had an allergic reaction. Where she rubbed her face, she developed a slight rash and an odd tingling and numbness. Any thoughts?
Many plants are not affected by the Juglone (the chemical in Black Walnut trees). http://ohioline.osu.edu/hyg-fact/1000/1148.html includes a list of plants that do and do not grow well with them. Your Mom is probably allergic to it, that caused the rash and numbness. Those are very unripe walnuts, they do have a fuzzy outside and fruity looking inside at that stage.
It looks to be a butternut tree, which is in the same family as the black walnut. https://www.extension.purdue.edu/extmedia/FNR/FNR-420-W.pdf
A friend in W. Virginia sent me some butternut to see if they would start and grow here Could not get any to sprout . Difference in black walnut and butternut is the shape of the nut. Black walnut is round and butternut is elongated. He also mentioned that it can cause a rash on some people while green. No problems after the nut falls from the tree. There are black walnuts everywhere here. I wonder why there is no commercial market for them? Unless its the difficulty in getting them out of the shell. My neighbor picks up several hundred pounds yearly but there is nothing one can do with them. Can`t even give them away.
Does the fruit change color when it is time to pick them? Also, does the Butternut tree have the juglone chemical too?
Yes, the butternut has juglone. It is in the same family as walnuts. I just can't tell you how it compares to the black walnut in concentration. I don't have any butternuts to have experience about them, but we just picked up the walnuts when they fell. then let them dry until Jan or so and then ran them through a corn sheller to get the husk off. then you can wash them and crack them. Maybe just google how to harvest them.
They have a bit milder flavor than a black walnut and thinner shell. An excellent nut. They will fall from the tree when ready to harvest but you still need to let dry if green shell remains. It will turn black and start to separate from the nut, then can be removed easily.
Ah yes, Black Walnuts. We have three of them. One in our backyard, and two on our side yard, and a few more babies that may get dug out. They have beautiful wood. But I hate them. I am always digging them out of my many flower beds where the squirrels have buried them. As I am typing this one of the Grey squirrels that frequents our yard has climbed up the tree and it bringing a nut down to bury somewhere. I'm not sure about why Black walnut meats are not harvested. I think they are somewhat bitter tasting if I remember correctly. It is interesting how some plants are effected by the Juglone in their roots. We have Black Berries planted right under the tree and they do super.