▁in ▁the ▁growth ▁of ▁certain ▁veget ation ▁types ▁such ▁as ▁forest ▁mant le ▁and ▁margin ▁communities . ▁ ▁Tree ▁layer ▁ ▁This ▁layer ▁of ▁veget ation ▁starts ▁from ▁a ▁height ▁of ▁about ▁five ▁metres ▁and ▁compr ises ▁the ▁top ▁str atum , ▁which ▁consists ▁of ▁ph an er oph y tes . ▁They ▁can ▁be ▁about ▁ 4 5 ▁metres ▁high . ▁The ▁trees ▁( and ▁sometimes ▁shr ubs ) ▁are ▁of ▁various ▁height s . ▁One ▁tree ▁has ▁its ▁crown ▁at ▁the ▁height ▁of ▁another ’ s ▁tr unk . ▁At ▁the ▁top ▁the ▁crow ns ▁of ▁the ▁different ▁species ▁of ▁trees ▁form ▁a ▁more ▁or ▁less ▁closed ▁can opy . ▁This ▁layer ▁creates ▁special ▁e colog ical ▁conditions ▁in ▁the ▁underlying ▁layers ▁of ▁for ests . ▁The ▁density ▁of ▁the ▁trees ▁determ ines ▁the ▁amount ▁of ▁light ▁inside ▁the ▁forest . ▁The ▁force ▁of ▁heavy ▁ra inf all ▁is ▁reduced ▁by ▁the ▁can opy ▁and ▁the ▁passage ▁of ▁rain water ▁is ▁fed ▁more ▁slowly ▁down wards . ▁The ▁tree ▁layer ▁can ▁be ▁further ▁sub div ided ▁into ▁the ▁upper ▁tree ▁layer ▁or ▁can opy ▁and ▁the ▁lower ▁tree ▁layer ▁or ▁under story . ▁ ▁Can opy ▁▁ ▁The ▁can opy ▁usually ▁refers ▁to ▁the ▁highest ▁layer ▁of ▁veget ation ▁in ▁a ▁forest ▁or ▁wood land , ▁made ▁up ▁of ▁the ▁crow ns ▁of ▁its ▁tall est ▁trees . ▁However , ▁individual ▁trees ▁growing ▁above ▁the ▁general ▁layer ▁of ▁the ▁can opy ▁may ▁form ▁an ▁emer gent ▁layer . ▁ ▁Under story