At least twice a week beginning three weeks prior to the anticipated start of greenup. Introduction The timing of greenup is usually influenced by temperature or moisture. Students will help by observing when greenup and leaf growth occurs on selected plants in the school Land Cover Sample Site. Your school site should be in an area where greenup of native plants is due to climatic factors such as increased temperature or precipitation. Watering and fertilization alter plants' greenup cycles, and the data would not be representative of natural vegetation and local climate connections.
Buildings absorb solar radiation and shelter sites from wind.
Therefore the urban environment can alter natural plant greenup cycles. Your greenup site can be the same as your Quantitative Land Cover Sample Site. If greenup observations at such a site are not practical, you may create a new Greenup Study Site which is more accessible. Since you will need to make frequent visits to the site, we suggest you select a site close to your school. Non-native species, called exotics, greenup cycles that are not necessarily tied to the local climate.