Nicky, if you have the test strips kit, then test it. How long before you would put cattle on it? If high in nitrates would it be better to disc it in and hope for a better year in 2022 or mix with other feed for winter feeding? How high in nitrates is the water the cattle drink? Are you harvesting the grain or leaving that as feed?
I would be surprised if your Triticale is at a dangerous level in nitrates since you didn't fertilize it. How much kochia and lambsquarter is mixed in? If used as pasture do your cattle eat much of the kochia and lambsquarter? What other grasses are mixed in?
It is a tough call this year because of the shortage of fall pasture and winter feed. Also, the ranges may be low on grass a month or more early, so the value of your triticale field rises and the best solution, in my opinion (if high in nitrates), would be to disc it in, losses financial merit. Step one is to test it, then consider other things like water that might add to the nitrate level. Borderline high nitrate levels have been known to cause abortions and other birth defects while not killing cows. This adds another consideration and argument for downsizing the herd so you have enough quality fall and winter feed.