Why is a Northern Green-striped Grasshopper brown and where are its wings? Some grasshopper species overwinter as nymphs and as a result their wings are not fully developed in February or March. This is a very common Chico species but unfortunately there was a major outbreak last spring and summer and as a result many of the young green ash trees were completely defoliated by this and a couple other grasshopper species. Although green-striped is part of its name, there are two color forms and the brown form seen here is much more common in Colorado than the green form. Birds who forage on or near the ground do consume numbers of these grasshoppers so maybe their abundance will be greatly reduced in 2017. This is the first grasshopper I have seen in 2017 on the Chico where as many as 60 might be seen throughout the year, some quite stunning in coloration.