Buying and Selecting Nursery Stock

Choosing high-quality nursery stock allows trees to establish quickly, grow evenly, and require less maintenance over their lifetime.

Download printable guide to features of a quality tree

Using Specifications

When purchasing trees, buyers can use specifications as a clear and enforceable measure to ensure that only high-quality, structurally sound trees are delivered. Specifications describe in detail what constitutes an acceptable tree. They also establish the conditions of inspection and time of delivery. By sending the nursery a copy of the specifications document linked below, buyers can request trees that meet these exact criteria. The specifications also give buyers the right to inspect trees upon arrival and reject any that do not meet this specification.

Key benefits of high quality nursery stock:

  • higher survivor rates

  • lower replacement costs

  • increased canopy cover

  • more compatible with urban and suburban landscapes

How to order a tree

• When you first contact nurseries, send them a list of the species, quantities, and sizes of the trees you want.

• Send the specifications document linked below right away, because if the nursery doesn't have trees that meet these specifications, you won't want to buy from them.

• Even if you don't feel qualified to judge tree quality, this document will ensure that the nursery understands what you want as a discerning buyer.
Download specifications PDF
Download specifications DOCX

Key traits when inspecting nursery trees

Start by looking at the crown.

The crown is the portion of the tree beginning at the lowest main branch extending to the top of the tree.

Download Illustrated Specs PDF

Central Leader

Planting quality trees begins by choosing vigorous, structurally sound trees from the nursery. Strong trees have straight roots, a thick trunk with taper, and a good branch structure appropriate for the species. Trees that become large at maturity are most durable when grown with one dominant trunk or leader to the top of the tree. The root collar or root flare (the point where the uppermost roots emerge from the trunk) should be in the top two inches of the root ball.

Making sure you have a quality tree before planting will save you a lot of time and effort.

Best: Original leader is retained on the tree and has not been topped.

Comparison of a small, thin branch and a larger, thicker branch with multiple smaller branches.
A leafless tree with thin, bare branches in a park, with a cloudy sky in the background

Acceptable: Original leader has been topped, but the tree has been pruned to create a new leader with at least one-half of the diameter of the original leader.

Diagram showing the steps of pruning a tree branch, including cutting the branch back to a specific point for healthy growth.
Bare tree branches against a clear blue sky.

Rejectable: Original leader has been topped and there are several codominant upward growing branches.

A diagram showing a thin, broken tree branch on the left and the repaired, full branch on the right.
A leafless tree with white streaks on its branches against a clear blue sky.

Branch Attachment

Acceptable: Main branches are evenly distributed, creating a stronger structure.

A black and white drawing of a leafless tree with many branches.
A young tree with no leaves surrounded by open land and a road in the background.

Rejectable: Main branches extend from the central leader at about the same area.

A leafless deciduous tree with numerous thin branches.
Tree with bare branches against a blue sky, with a house and power lines in the background.

Branch Size

Acceptable: Branch diameter about one half the diameter of the central leader, as measured 1 inch above the branch union.

A black and white drawing of a tree trunk with a fork in the branches.
Person pointing at a young tree with green leaves in an outdoor nursery or garden.

Rejectable: Branch diameter is larger than two-thirds the diameter of the central leader, as measured 1 inch above the branch union.

A simple line drawing of a tree trunk with textured bark and a small branch.
Person's hand pinching a young tree branch with a blue ribbon tied around it, surrounded by green foliage.

Inclusions

Inclusions are bark embedded in the union between a branch and the trunk or between two or more stems that weakens the union by preventing the formation of a normal branch bark ridge.

Acceptable: The branch extends away from the trunk and a bark ridge forms at the juncture.

Simple black and white drawing of a tree trunk with two branches.
Close-up of a plant stem wrapped with green tape, with a broader plant stem or trunk nearby, showing the natural texture and color of the plant.

Rejectable: Bark appears to be growing inward at the attachment point, indicating a weak attachment.

Black and white line drawing of a tree trunk with a branch splitting off.
Two tree trunks wrapped with a teal ribbon tied in a bow

Temporary Branches

Acceptable: Small (<3/8”) branches are present on the trunk below the lowest main branch.

A drawing of a leafless tree with multiple branches.
A tall tree planted in a large pot against a clear blue sky.

Rejectable: The lower portion of the trunk is bare. Clear trunk takes up more than 40% of the total height of the tree.

A simple drawing of a leafless tree with multiple branches on a white background.
Young tree planted in a black pot, supported by a wooden stake with a green tie, situated along a dirt path in a nursery.

Look at the tree trunk.

The trunk is the main stem of a tree, beginning at the root collar and ending where branches begin.

  1. Trunk is free of wounds, conks, sunburned area, and signs of insect damage

  2. Caliper (trunk diameter)

    Tree trunk is thick enough with enough taper for the tree to remain vertical without a stake. Trees in #5 containers may require stakes to hold them erect.

Diagram of three trees showing desirable and not desirable pruning cuts. The first tree labeled 'Desirable' has well-spaced branches and a balanced shape. The second tree labeled 'Not Desirable' shows improper pruning with cuts made too close to the trunk, resulting in poor branch arrangement. The third tree, also labeled 'Not Desirable,' depicts excessive leaning and poorly placed cuts.

Check on the roots.

Root Defects

Acceptable: The root collar and the inside portion of the root ball are free of defects, including circling, kinked, and stem girdling roots.

Rejectable: The root ball has been imprinted by the smaller propagation container causing defects including circling, kinked, and stem girdling roots hidden on the interior.

A defected root system may inhibit the growth of a tree, cause it be unstable, or lead to its death.

Root Distribution

Acceptable: : Roots on the periphery and bottom of the root ball have a diameter less than indicated in the chart below. The maximum acceptable root diameter on the periphery should be indicated in the nursery stock specification.

Rejectable: Roots on the periphery and bottom of the root ball have a diameter more than indicated in the chart below. The maximum acceptable root diameter on the periphery should be indicated in the nursery stock specification.

Root Moisture and Distribution

The tree shall be well rooted in the soil media (substrate). Root distribution shall be uniform throughout the container media. Structure and growth shall be appropriate for the species/cultivar. When the container is removed, the root ball shall remain intact. When the trunk is lifted both the trunk and root system shall move as one.

At the time of inspection and delivery, the root ball shall be moist throughout. The crown shall show no signs of moisture stress as indicated by wilted, shriveled, or dead leaves or branch dieback. The roots shall show no signs of excess substrate moisture as indicated by poor root growth, root discoloration, distortion, death, or foul odor.

Tree Selection Details and Specifications

See all details and specifications

Check out these webpages for even more information

Digital illustration of young plants with green and yellow leaves growing in grey containers.
Illustration of two potted trees with different colored leaves, one orange and one green, indicating different seasons.

Growing plants in a nursery

Choosing a tree species

Close-up of a wooden carpenter's square with black and brown wood on a black background.

Pruning at a tree at all ages

A leafless tree in the center with a brown trunk and black branches, surrounded by concentric circular lines in the ground, against a background of orange and dark brown abstract shapes.
An illustration of a person planting a tree bulb underground with tools, and arrows showing root growth and soil warming as part of tree planting and soil health process.

Caring for a young tree

Planting a tree