Fly agaric grows around a number of tree species.
The severe winter and short growing season limit the number of tree species.
A number of tree ferns have become quite rare as a result of overcollection by humans.
By far the greatest number of tree species are dicotyledons; they are represented by such familiar groups as birches, elms, hollies, magnolias, maples, oaks, poplars, ashes, and willows.
A tall crown and few to no lower branches is a strategy a number of tree species employ to reduce wildfire damage.
Officially, Hurricane Sandy caused the highest number of tree casualties of any storm since 2002, when New York instituted its 311 line for nonemergency calls.
A diverse number of tree families and species develop buttress roots, suggesting that they are induced by the environment and are of some adaptive advantage.
Woodland across the UK is under threat from a number of tree diseases, including the arrival last year of ash dieback, which seriously damages and kills large numbers of ash trees, an important native species.
The association between number of tree planted and fuelwood was statistically insignificant.
To be practical, the number of tree size and species categories should be kept lowb.
The number of tree species had a vital effect on tree size heterogeneity.
