thats a lot of large trees for a half acre .. of which i presume...the house, driveway and garage probably take up a lot of space ... and your list of favored plants.. all seem to be full sun lovers ...

there are a lot of reasons for an orchard to go into decline .... my attempts at such rarely lasted more than a few years..

remind us where you are???

ken

THANKS KEN!! I was waiting for your response. SW suburbs of Chicago. The wooded areas are along the back of the property. There is an empty lot next door that is cottonwood, oak, and another tree I do not know. The front only has 2 river birch and is pretty sunny. There is large area in the back (their orchard) that is also quite sunny. There is a small patch long the house too that is in full sun behind the garage.

I have a 150' long thicket of black walnuts on a property line. It amazes me the number of things which do grow in there. Invasive burning bushes and hoeysuckle don't care for sure. Neither do wild grapevine, elderberry, redbud or white ash.

So I went past the house and noticed the bulk of the trees are not necessarily black walnut. There definitely enough specimens within the border, which seems to be mixed with oak and maple. I am thinking if I notice the border deteriorating, I can remove the black walnuts as needed since they don't seem to be that large.

It seems the type of soil will greatly affect whether pines can grow alongside black walnuts or not. My parents have eastern white pine and black walnuts side by side on three different areas of their property. It's been 30 years and not one pine has died or shown ill-effects yet from its neighboring tree. Will this continue for the next 100 years? Can't say.

"A study with white pine (Pinus strobus L.) suggests that poorly drained soils may exacerbate the effects of juglone toxicity: pines growing near black walnut on a well drained soil grew tall, while pines growing near black walnut on a poorly drained soil died."

https://walnuts.pbworks.com/f/Scott+%26+Sullivan+blackwalnut.pdf

If the trees are small just remove them, if you are big into veggie gardening it will be worth it. My neighbor has white pines next to a black walnut in a low spot and both are growing well, but a nearby crabapple loses almost all its leaves every year. I have smaller ones at each corner of my property and find it inconvenient. Vaccinium and Kalmia are natural understory plants here and I cant grow them because of these trees. The chainsaw is warming up in my mind as I type this. Their presence seems to promote weedy plants that can grow in their shade, like the aforementioned burning bush and honeysuckles, perhaps due to the absence of juglone sensitive plants.

I live in Missouri, Black Walnut Capital of the USA..all kinds of stuff grows under walnuts here. It's not a science.

here is a good article on Garden myths and that walnuts are not a huge problem

https://www.gardenmyths.com/walnuts-juglone-allelopathy/

The Walnut Myth

joeinmo, my area could give MO a run for its money, at least in lower elevations. B walnuts are everywhere & even form pure stands. They even climb up slopes & compete in the oak/maple forest. They are the weediest tree on my lot -- even worse than Siberian elm.

We have several very old black walnut trees. In general, they are a mess. Between the walnuts everywhere, the squirrels make a mess out of them leaving piles all over and when the leaves fall they cover everything for weeks. But, they are quite lovely to look at.... on someone else's property. :-/

Don't cut them down! Black Walnuts are a wonderful native that are both edible and medicinal (their hulls being renowned for parasite cleansing)! You're lucky to already have some on that property!

Black walnut are a rare combination...long lived North American native shade trees that produce something edible and particularly valuable lumbar. I don't understand people who want to cut down things that took a century to grow to plant a few annuals.

Black walnut toxicity is exaggerated. Oak laughs at black walnut. Pine and apple trees unfortunately are rather acceptable.

What about planting American Holly? A native evergreen that isn't bothered by black walnut.

Sugar maple strangling a black walnut -- the walnut was visibly declining w/the foliage scant:

thanks for all the information everyone. I've been reading a lot since I posted and decided to wait a little bit and observe the growth of the nearby trees. The main issue is I'd like some conifers for winter privacy and the lot is a little bigger than I thought. I might be okay with some selective pruning or editing and some well-placed evergreens for privacy. The oaks and other trees growing nearby seem to be in good health. I think I will watch and wait for a few years and not be in such a hurry with the chain saw.

as a follow-up I learned that Arborvitae (Thuja), hemlock (Tsuga), and Chamaecyparis obtusa seem to not mind juglone. I've also read cryptomeria and Metasequoia can tolerate as well. I've left all trees intact and selectively removed weeds, broken branches and rubbish. Looking forward to a bumper crop of black walnuts (with some to share with the squirrels). I don't have room for large Norway Spruces but my neighbor wants some for his lot which is near-treeless and open to the road. I spent the winter thinning out and pruning and am so excited for the new planting season. thanks all