M. Huston (1994b) pointed out that the well-documented pattern of increasing ann

M. Huston (1994b) pointed out that the well-documented pattern of increasing annual primary production from the poles to the equator is strongly influenced by the longer growing season at low latitudes. The following data are from table 14.10 in Huston. The data cited by Huston are from Whittaker and Likens (1975).
Annual    Length of       Monthly
NPP       Growing Season    NPP
Forest Type             (t/ha/yr)    (months)       (t/ha/mo)
Boreal forest             8       3          2.7
Temperate forest          13       6          ?
Tropical forest          20       12          ?_______   

Complete the missing data to compare the monthly production of boreal, temperate, and tropical forests. How does this short-term perspective of primary production in high-, middle-, and low-latitude forests compare to an annual perspective? How does the short-term perspective change our perception of tropical versus high-latitude forests?