m3/ha converted to tonnes

hi there, could any one help me with this conversion. its for tree mass, i need to convert m3/ha to tonnes and am finding it very difficult. is density a factor?
thank you

[JohnS]

Originally Posted by Unregistered

hi there, could any one help me with this conversion. its for tree mass, i need to convert m3/ha to tonnes and am finding it very difficult. is density a factor?
thank you

Yes, trees have widely different densities. For wood (dried for use as lumber) densities can range from 0.2 g/cm³ for bamboo to 1.3 for lignum vitae. For more reasonable species, 0.7 g/cm³ might be a VERY rough estimate.

For fresh cut trees, the sap will likely make a difference. But if your tree floats, it is less than 1.0. Note: All of the g/cm³ figures are also t/m³.

I think as a minimum, you would need a density from a reference book or by sample measurement for each species, and an analysis of what species composition is on the property. There may be some industry guideline, but I don't know of them.

What does it mean m3/ha ?? it is stand for want any one can reply

[JohnS]

Originally Posted by Unregistered

What does it mean m3/ha ?? it is stand for want any one can reply

The three should be a superscript. It means cubic meters per hectare. The 3-superscript can be represented in special symbols, m³/ha, but a lot of people just type it after the unit, or use a caret, m^3/ha.

It might be suitable for volumetric yields such as timber mass or for irrigation water requirements, as examples. (25 mm of water would require 250 m³/ha)