when your growing slimply look at the fan leaves sativa's are from tropic arera so the grow taller to compete with other plants VS indica's originate from mountain regins where there higher elavation an less air to breath so they are short n stalky to conserve energy... SATIVA"S have big or small but always skinny or slim fan leaves cause they are always moist n it rains alot in those area so slimmer leaves mean less run of water to worry about.... INDICA's need bigger fan leaves cause they need more air to breath and more light for more energy to survive the altitude n bigger leaves to stay moist .... they can both produce dense bugs thats just good drying...