ABSTRACT
This chapter talks about the potential cases of plant memory: the flytrap's two trigger hairs; the integration of gravitropism and thigmotropism in roots; photoperiodism; and stem thickening in response to a windy environment. Photoperiodism is an apparent case of plants remembering. Photoperiodism is growth (particularly flowering) in response to the amount of light to which the plant has been exposed. To be either short-day or long-day, it seems plants must somehow remember how much light they have encountered. When the second hair of the flytrap is touched, and the lobes fold together, that is something the plant does, a 'procedure' it goes through, but the authors have no reason to think that this is something the plant remembers rather than something the plant simply can do. Plants and their parts—their shoots, roots, leaves, cells—encode weak information about their environment simply because they correlate with parts of their environment.
