Young trees in new subdivisions: the first ten years

Newer neighborhoods in Spanish Springs, Cold Springs, Dayton and Gardnerville started with a row of small builder trees. Ten years on, those trees either have a good shape or a problem that costs real money to fix.

How young are these neighborhoods and their trees?

The Census Bureau's American Community Survey puts the median year built at about 2002 in Spanish Springs and about 2004 in Cold Springs. Trees planted with the houses are now roughly twenty years old at most, and many were planted later. They have outgrown the stakes and the nursery tags.

The ISA notes that the soil in dense urban areas and new subdivisions is often disturbed, shallow, compacted and subject to drought. That shapes what the first decade looks like.

What pruning does a new tree need?

The ISA says to limit pruning of a newly planted tree to removing dead or broken branches, and to hold off everything else until the second or third year, when the tree has recovered from transplant stress. After that, the goal is a strong central trunk with sturdy, well-spaced branches.

Most young trees keep one dominant, upward-growing leader. Do not cut back the tip of the leader. When two nearly equal leaders compete (codominant stems), the ISA recommends removing or shortening all but one while the tree is young. Branches with narrow angles can enclose bark, called included bark, which weakens the attachment as the tree matures, and the ISA advises pruning branches with weak attachments while they are small.

• Set an objective for each cut
• Cut just outside the branch collar
• Do not remove too many branches at once
• Do not use wound dressings

How much clearance and spacing should it have?

The ISA gives some numbers. The lowest permanent branch depends on where the tree stands: about 8 feet of clearance is enough in most settings, and the street side of a street tree may be raised to 16 feet. Space between permanent branches should be about 3 percent of the tree's eventual height. Keep some branches in each direction, and do not let one scaffold branch grow directly over another.

What about mulch, water and the lawn?

Mulch 2 to 4 inches deep, kept off the trunk, is the ISA's recommended range. Mulch against the trunk invites problems, and a thick layer of fine mulch can mat. A mulched ring also keeps string trimmers and mowers off the bark, which is a common young-tree injury. See mower and string-trimmer damage.

Watering needs for high-desert trees are in our watering guide.

When should I call an arborist?

A visit around years three to five is the cheapest time to fix structure, because cuts are small. If you have a row of the same species, the whole row will need the same attention. A certified arborist can walk the yard and tell you which trees need work and which need only time. Call 775.232.8243 for a free estimate or see our tree trimming and pruning page.