It's tree time! The chartreuse of unfurling foliage can act as a trigger leading to irrational urges and impulsive actions!  While winter is known to be a time for dreaming and planning, springtime is an altogether different matter. The past few months of flowers and fragrance have us running to the garden centers, buying left and right.

Two words: SLOW DOWN…let the morning coffee wear off. Peruse your gardening notes;  review what you dreamt of accomplishing in those calmer winter months. In the case of trees, you truly are planting-and planning- for the future. That fabulous tree with muscular branching and smooth brown bark looks hot in the pot, to be sure. But will it seem half as alluring six times larger, ten years later, battle-scarred by the chainsaw ?

Look at available space before you even bring your new tree home. Select a tree that can grow to its a mature size in the allotted space without annual severe pruning. Consider existing obstructions such as the neighbors' trees, overhead power lines, streetlights or fences.

We must acknowledge the limitations of hard Colorado soils. Few trees thrive in the low-oxygen condition of our heavy, slow draining and dense clays. High salts and alkalinity are also limiting factors. This can be somewhat mitigated by amending and loosening soil with manure or compost.

Improving the soils will open the door to broader possibility. That is where we can indulge our feverish spring desires,  and fall prey to beckoning call of the sirens of vixens of nursery-land.

Need to block winds or awful views? Pinyon pine is a medium-sized, slow grower that thrives in xeriscapes. Up close, ponderosa pine bark smells of an intoxicating, sun-baked vanilla. Scotch pine can tolerate the extra water of turf irrigation and grows quite rapidly, reaching outward with its broad spreading muscular arms.

To shade your driveway or cool your home in the summer, large deciduous shade trees are perfect. Choose a tree that matches your tastes for maintenance (clean up of brittle twigs and limbs) and complements your home and landscape. Consider bark colors and textures. Foliage can vary in its hues from bright new greens to cooler blues. Think about tree forms: columnar, compact lindens fit in tighter spaces. Broad and spreading trees, such as hackberry or oak, embrace the horizontal, connecting sky and plain. Vase forms can be uplifting and graceful, like dainty crabapples or the elms on The Oval at the Colorado State University campus.

Want to be tickled by the playful song and chatter of birds? Flowering trees entice with fragrance and nectar; later fruiting satisfies avian hunger. Diminutive trees can bring the activity even closer to your patio or window. Hawthorns and serviceberries are irresistible. Dwarf fruit trees such as cherries work too. Thick foliage allows for nesting and cover. Rocky Mt. juniper comes in so many forms nowadays you can find just about any to match your site. The birds seem to appreciate its safety around their backyard feeders.

Once you match function, fit and form, it's simply a matter of choice! Ask your Master Gardener or nursery professionals for help in choosing the perfect tree for your pre-determined spot. Harness the energy of spring power and passion for the digging of the hole.

For more information on choosing trees for your location, see fact sheets #7.403 Evergreen trees for Colorado landscapes, #7.419 Large deciduous trees for street and shade, #7.418 Small deciduous trees for privacy and color and #7.408 Trees for mountain communities.

Q: I've heard of an insecticide to control caterpillars called Bt?  What is this and will it also kill other insects?

A: Bt, or Bacillus thuringiensis, is a type of bacterium that kills leaf-eating caterpillars. It effects their digestive system and eventually kills them. It will not harm beneficial insects, people or pets. Since it must be eaten to be effective, dust both sides of plant leaves when caterpillars are present.  Be sure and purchase strains of Bt that are effective against the specific target pest.

Q: Is it safe to use newsprint as a mulch in the garden?

A: Most ink used on newspapers today is soy based and will not harm soil or plants. Avoid using paper that is glossy and colored as it might contain heavy metals that could be taken up by the plant. At the end of the season, try covering it with hay or straw and till it all under.

Q: It seems like I get fewer fruit from my cucumbers, squash and other vines each year. I'm sure they get enough water. Any ideas?

A: The vegetables mentioned must be pollinated to produce fruit. Try attracting bees by planting flowers nearby that they like. A few are cornflower, cosmos, coneflower and black-eyed Susan. Herbs that are favored by bees include coriander, mint, beebalm and hyssop.

If you are having trouble with overly wet or dry areas in your yard due to a poor irrigation system, call (970) 221-6877 to sign up for a sprinkler system irrigation audit. This is a free service that will help pinpoint problem areas, malfunctioning heads that you will need to have repaired and also give you estimated watering times for each station.  This is a free service  for City of Fort Collins water customers only.

To save water, irrigate at ground level.  This minimizes evaporation and prevents water from being sprayed onto hard surfaces.  One way to do this is with a soaker hose that you can create inexpensively by simply putting holes into your existing hose.

With summer comes a lot of construction and outdoor activities. Some of the leading causes of tree root damage are trenching, paving, changing the soil height, soil contamination and compaction.  Since most tree roots are in the top foot of soil, think twice before doing construction projects that will harm tree root systems.  For more information on how to protect tree roots, call the Larimer County Cooperative Extension office at (970) 498-6000 and request fact sheet #7.420 Protecting trees during construction.

The authors have received training through Colorado State University Cooperative Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.

Gardening and Insect Fact Sheets are available on-line by clicking HERE.

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This page updated:  June 4, 2003