|Credit/ Bob Yoder|
Picking parts off a trillium plant can kill it even if the rhizome is left undisturbed. Some species of trillium are listed as threatened or endangered and collecting these species may be illegal. Laws in some jurisdictions may restrict the commercial exploitation of trilliums and prohibit collection without the landowner's permission. In the US states of Oregon, Michigan and Minnesota it is illegal to pick trilliums. In New York it is illegal to pick the red trillium.
It is illegal to in any way injure the common Trillium grandiflorum (white trillium) in Ontario, though there are two exceptions: a person will not be fined if the person is a public works employee carrying out their job on public land, or the person is a private citizen carrying out "necessary work" on land the person owns or lawfully occupies. The rare Trillium flexipes (drooping trillium) is also protected by law in Ontario, because of its very small Canadian population.
High white tail deer population density decreases or eliminates trillium in an area