WINTER IS THE PERFECT TIME to consider the trees - or the lack of them - in your yard. The first challenge is to decide which trees will stay. Sometimes, trees must be removed for the health of neighbouring trees, or the safety of buildings and people. My tree inventory includes an enormous Norway Spruce (Picea abies) that was planted in front of the house in the 1920s. Theoretically, it is in the wrong location. We face south, and the rule is to plant deciduous trees on the south side to provide summer shade while allowing the sun's rays to warm the home throughout the winter. But the spruce will remain there because it has earned right of ownership. Years ago, I planted white cedars (Thuja occidentalis) to the west and Norway and White Spruce (Picea glauca) to the north to protect our home from the winds that often lash up over the nearby fields. I am particularly fond of the Shagbark Hickories (Carya ovata) that line the roadway. These native beauties survive whatever nature throws at them, because this is their territory. I suggest that you take a look around your neighbourhood to identify native tree species that thrive in your climate. Local nurseries can also provide this information. Next, figure out where you need trees. You might consider planting some along laneways, fences and roads; in areas that are difficult to cultivate or mow; on steep slopes to control erosion; and where shade or wind protection is necessary. During the winter months, notice where the winds drop snow, leaving drifts on lanes or in front of buildings. When you are planning a windbreak, visualize a snow fence. Snow drops on the leeward side (opposite the prevailing wind direction) of the fence. The same thing will happen with trees, so plant windbreaks far enough away that the resulting snowdrifts will not cause you more work with a snowplow. In the past, I planted windbreaks in straight lines. If I were starting again, I'd be more creative! Grouping trees in threes, fives or sevens can break the prevailing wind and offer glimpses of surrounding countryside. Be sure to take the tree's mature size into consideration when you plant. It is demoralizing to have to remove some of the trees within a decade when it becomes obvious they are growing too close together. Mulch the ground around the trees with wood chips or local stone to retain moisture, discourage weeds and reduce damage from mowers. Finally, consider the autumn foliage. Is there a variety, or do most of your deciduous trees turn a pale yellow? Throw vibrant splashes of colour and texture into your landscape by including such trees as Red Maple (Acer rubrum) or Serviceberry (Amelanchier sp.) Don't forget to take advantage of the needle colours on evergreens, as well. These vary from blues to dark and medium greens as well as yellow. It's worthwhile to plan for the impact of the fall colours. Every year, they'll cheer us on during the last days of the growing season and into early winter. - SUSANNE SPENCE WILKINS