Oops - how did this get here on this thread??? Posted on another thread…
If you are in the US your sycamore is most likely a true sycamore (Platanus occidentalis) and not toxic to horses
The link you posted is from the UK where they call sycamore maples sycamores (Acer pseudoplatanus) and they are toxic
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Oh I hope so ! I am in the US. It’s such a lovely tree.
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Acer pseudoplatanu does exist in the US
Acer negundo is another tree that’s in the US which can cause the same atypical myopathy/seasonal pasture myopathy.
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It does but not prolifically and we don’t call it a sycamore here. Acer is the genus for maple BTW not sycamore
This is what I do for a living
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A good link with the differences.
If you have what Americans call a “sycamore” it’s likely either an American Sycamore or a London Planetree, neither of which are toxic.
Most everything in the Acer genus has some potential for toxicity to horses related to the red maple disease.
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My favorite part of looking up every single weed that pops up in my pasture is reading that they are toxic but highly unpalatable and only a horse with no other forage would consider eating it…and then watching my horses, with unlimited grass, two meals a day and free choice hay hold eye contact with me as they chomp down on said weeds….
For tree questions in general, you might try getting in touch with your states natural resource agency to see if they have a forester in your area. They are usually happy to do site visits.
Also, if you are looking for a source of very inexpensive trees, many states have nurseries (usually native trees but my state has non-natives as well). The Iowa State Forest nursery actually ships trees out of state and the prices are extremely reasonable (and they have bald cypress). Not sure if the prices are still up right now (they take orders in spring and fall only) but they are about $1 - $1.25 a tree.
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Most of what’s called “sycamores” in the US are various species that aren’t a problem. Having said that a few years ago a pony belonging to someone I know got sycamore poisoning in the midwest. The owner, barn manager and their farm vet had never heard of it. The trees had apparently been on the farm for years without problems. They were ornamental and planted but so far in the past no-one remembered when. It was diagnosed pretty swiftly at the equine clinic though and they saved the pony.
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Yes, Acer = maple. The problem is that particular one is also called colloquially “sycamore maple”, at least in the UK, which is confusing.
The one I just planted is a London planetree. Apparently there’s a disease that made American sycamores a thing of the past? I don’t know. But I couldn’t locate one, so planetree it is.
There’s a sycamore anthracnose that takes out most young sycamore trees planted in landscaping situations. The London Planetree isn’t affected by it. Most of the time when you see a sycamore planted as part of landscaping, it’s a London Planetree. They are virtually indistinguishable. It’s been that way for a long, long time.
But native American Sycamores still thrive in natural locations.
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At my childhood home, still in the family as it’s now owned by my sister, there are two VERY old American Sycamores. One was struck by lightning 20 years ago and is still healthy and growing.
They were mature trees when the house was purchased 34 years ago, and are still kicking. Love that giant canopy!
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They honestly could have been planetrees.
I took some classes, including a dendrology class, at a university whose streets were lined with “sycamores” planted in the early 1900s. But they were actually London Planes.
They are pretty much impossible to tell apart unless you look closely. Plane trees’ bark is mottled everywhere where sycamores are lighter at the top and darker at the bottom. Plane trees also have the seed balls in pairs or clusters.
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Definitely American Sycamores. I had an arborist take a look when I started down the path of trying to find one to replicate them. Alas, it wasn’t to be - so I went with what would work!
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You really won’t be able to tell the difference in the end!
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I hope it grows fast, and its root system too! It got put in this spring and is getting the standard “first year babying”, and looking good so far.
Even if it’s not exactly the same, that’s alright. I’ll just be silently jealous of my sister’s. 
To bring this full circle, this tree is ok to plant in the pasture? Or no? I’d love to get some shade trees started out there.
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It’s fine to plant in the pasture.
And I promise you, plane trees grow the same. The leaves are identical. The overall look is the same. You can only distinguish them apart when you get nitpicky!
I love trees and geek out over different types. Although I am absolutely shit at growing them. 
I planted maybe 10 last year and only 1 survived. 
So I’ll just keep admiring the ones I already have plus other people’s.
My sycamore in my backyard, which I was really surprised it’s a sycamore. But I live in a swamp, so…
Now if someone could tell me how to get the poison ivy off the trunk I’d be golden.
And bringing it back to the subject of the thread, the bald cypresses behind my paddock at my last farm (one right in the center):
And my horse covered in bald cypress needles:
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How thick is the base? Is it pullable? How high up does the vine go?
If too thick to pull, then cut it close to the ground. Pull the rest of the vine off if possible (and yes, this does require a good clothing setup, either a plastic “suit” or old/cheap clothes you can toss, or being willing to soak said clothes in some Dawn for a bit. Honestly, I’ve washed a lot of clothes that got brushed by PI, in the water, normal detergent, but I also always put a swirl of Dawn in, and never had an issue (and yes I’m highly allergic to the stuff)
Then paint/spray the stump with Roundup Poison Ivy or if you have something else that has triclopyr in it, use that. Keep an eye for any shoots coming off ground-level vines you missed.
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Of the tree or the poison ivy?
Either way, pretty thick. It’s not pullable. And the vines go well into the canopy. I’m not sure my tallest ladder would reach.
Thank you for the protocol! I’m highly allergic,
too so I haven’t messed with it much.
Stupid question, but won’t any vine that can’t be pulled still survive even if cut off thanks to the sucker shoots they sprout?
