trees

Get involved with community activites such as planting native trees in your area.

Theres always somthing which needs to be done- planting trees, weeding the area so that the trees can grow, watering them etc.

Plant your own fruit trees, in a couple of years you'll have the beginnings of the best fruit you've ever tasted. Tree ripened fruit is much nicer than stuff that's picked early and then freighted. There won't be any freight costs, most pests can be dealt with naturally and you'll save money on your grocery bill.
Some ideas of trees to plant: Plum, peach (the older varieties are more disease resistant), almonds, apples, pears, lemons etc.

Protecting forests and planting new trees contributes to the absorption of carbon dioxide from the air. Plant trees in your garden, join in community re-vegetation projects, replace that concrete backyard with vegetation.

Make sure that any wood products (furniture, paper etc.,) is sourced from plantation forests or certified sustainable forestry.