Channell crossed the Asiatic species Trillium camschatcense with several North American species. Of those, the crosses with T. erectum, T. flexipes, and T. vaseyi produced solid, seemingly viable seed. Seeds of the cross between T. camschatcense and T. erectum flowered in 9 to 10 years. Disease Various Trillium species are susceptible to a greening disorder caused by bacterial organisms called phytoplasmas that alter the morphology of infected plants. Symptoms of phytoplasma infection include abnormal green markings on the petals (floral virescence), extra leaves (phyllody), and other abnormal characteristics. Infected populations occur throughout the species range but are prevalent in Ontario, Michigan, and New York. For many years, this condition was thought to originate from mutation, and so many of these forms were given taxonomic names now known to be invalid. In 1971, Hooper, Case, and Meyers used electron microscopy to detect the presence of mycoplasma-like organisms (i.e., phytoplasmas) in T. grandiflorum with virescent petals. The means of transmission was not established but leafhoppers were suspected. , the insect vector for Trillium greening disorder is unknown. Phytoplasmas were positively identified in T. grandiflorum and T. erectum in Ontario in 2016. Phylogenetic analysis supported the grouping of the phytoplasmas isolated from infected plants as a related strain of &apos;Candidatus Phytoplasma pruni&apos; (subgroup 16SrIII-F) with 99% sequence identity. This subgroup of phytoplasmas is associated with various other diseases, including milkweed yellows, Vaccinium witches' broom, and potato purple top. Conservation 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 Michigan and Minnesota it is illegal to pick trilliums. In New York it is illegal to pick the red trillium. In 2009, a Private Members Bill was proposed in the Ontario legislature that would have made it illegal to in any way injure the common Trillium grandiflorum (white trillium) in the province (with some exceptions), however the bill was never passed. The rare Trillium flexipes (drooping trillium) is also protected by law in Ontario, because of its decreasing Canadian population. High white-tailed deer population density has been shown to decrease or eliminate trillium in an area, particularly white trillium. Some species are harvested from the wild to an