Transplant planner

How to move a tree

• Prune the roots ahead. University of Maryland Extension starts root pruning in early fall, six months to a year before the move and ideally two years. Clemson Cooperative Extension cuts a trench at the ball's edge and refills it, in March for a fall move and in October for a spring one.
• Dig moist soil. Iowa State University Extension digs when the soil is moist, and waters the spot 3 to 4 days ahead if it is dry, so the ball holds together.
• Tie in the branches and mark north. Clemson Cooperative Extension ties up low branches with twine before digging. It marks the branch that faces north and the soil line on the trunk, so the tree goes back the same way at the same depth.
• Cut the ball. Iowa State University Extension marks a circle about 6 inches wider than the ball and cuts straight down 9 to 12 inches, the back of the spade toward the tree. It trenches outside the circle, shapes the ball and undercuts it at 45 degrees.
• Wrap it, or slide it onto a tarp. Clemson Cooperative Extension wraps the ball tightly in burlap so it does not dry or crumble. Iowa State University Extension uses a tarp in its place when the tree goes straight back in the ground and the ball is firm.
• Lift by the ball, never the trunk. University of Minnesota Extension lifts a balled tree from beneath the ball, never by the stem. Iowa State University Extension finds hand carts useful for the heavier balls.
• Replant at the same depth. Iowa State University Extension digs the new hole two to three times as wide as the ball. University of Minnesota Extension sets the trunk flare about an inch above the soil.
• Water until it roots in. The years to root in come with the answer above, and the watering calculator gives the schedule for a balled tree of the same trunk.
• Check the new spot first. The planting-site check says whether the species will thrive where it is going.

Root balls by trunk size

The standard's balls for Type 1 shade trees, Table 3, with the next larger size for a tree that grew where it stands and the depth the standard prints for it. Weight is a straight-sided ball of moist loam, and the lift is the Health and Safety Executive's.

The root ball follows the American Standard for Nursery Stock, ANSI Z60.2-2025, which AmericanHort publishes. Tables 3 to 6 size trees, Tables 9 to 12 deciduous shrubs, and Tables 13 to 24 conifers and broadleaf evergreens, each with a minimum width and depth. A size names the least of its interval, so a trunk of 1.2 inches takes the 1-inch row. For a tree dug from the ground, the standard asks for "the next larger size interval shown in the appropriate table for nursery grown stock". Its glossary counts one "taken from an established landscape planting" as collected, so a tree in a yard qualifies. Clemson Cooperative Extension's table for moving established trees, from the American Association of Nurserymen, gives the same step up for shade trees from ¾ inch to 2 inches. A natural evergreen goes by its height, and the planner reads its caliper rows only past 9 feet. Where the standard names a species or genus in its type examples, that decides its table. Black gum and white oak are Type 2 shade trees, flowering dogwood a Type 4 small tree and wild hydrangea a tender shrub. Elsewhere a slow-growing tree is read as Type 2, the standard's slower growers, its own reading. The 2004 edition, as the Indiana Department of Natural Resources posts it, had the same widths for trees and shrubs, no printed depths, and smaller balls for upright evergreens from 3½ inches.

Iowa State University Extension's table, from Watson and Himelick, gives the nursery width and a deeper ball: 75 percent of the width under 20 inches, 67 from 20 to 30 inches and 60 beyond. Its table and Clemson's give smaller balls for shrubs and spreading evergreens than the standard does. The planner follows the standard, the figure nurseries are held to, and shows both beside it. Clemson and Iowa State give a tree that is hard to move a larger ball, without a figure. Clemson names beech, hickory, sweet gum, hornbeam, sassafras, tupelo, walnut and white oak as trees that are difficult to move. The Morton Arboretum has pages on 128 of our trees and shrubs. Many rate how well each transplants, and some say why in a sentence, which the planner quotes. Where the two disagree, the planner takes the cautious reading.

Kansas State University's Soil, Water, and Plant Relationships tables each soil's bulk density and the water it holds, from the Natural Resources Conservation Service. Sand weighs 1.70 grams per cubic centimeter dry and holds 7 percent water, loam 1.55 and 22.6 percent, and clay 1.35 and 28.8 percent. A ball dug moist holds about that water, so a cubic foot weighs about 114, 119 and 109 pounds. The planner weighs a straight-sided ball, its own reading, and a ball rounded at the base weighs a little less. Iowa State University Extension gives the weights in figures: "A 12-inch soil ball may weigh between 30 and 60 pounds, a 24-inch ball may weigh between 250 and 400 pounds, and a 36-inch ball could weigh more than 1,000 pounds." The Missouri Department of Conservation lists 185 pounds for a 1¼-inch tree's ball, 225 for 1½ inches and 390 for 2 inches, a little under the planner's figures. Clemson says: "A ball of soil 15 inches in diameter and 15 inches deep may weigh 200 pounds or more."

Who lifts it follows the team bands of the Health and Safety Executive's Manual handling assessment charts. Two people are in its green band under 35 kilograms, about 77 pounds, and its amber band to 65 kilograms, about 143. Four people are green under 75 kilograms and amber to 130, about 165 and 287 pounds. For a team of five or more it asks for a full risk assessment. The planner stops at the top of amber, its own reading, since red asks for prompt action. Iowa State says a ball wider than 24 inches generally takes mechanical equipment, and may call for a professional. Its yard and garden page says: "Home gardeners should limit themselves to transplanting trees with a trunk diameter of 2 inches or less." University of Minnesota Extension matches a 44-inch tree spade to a deciduous trunk of 2 to 3 inches, a 66-inch spade to 3 to 5 inches and a 92-inch spade to 6 to 8 inches. Iowa State has two people lift a smaller ball by the corners of its burlap, and the planner holds a heavy one to the bands.

University of Maryland Extension says: "Transplant trees and shrubs when they are dormant." It goes on: "In Maryland, there are two transplanting seasons: mid-to-late fall, and late winter to early spring, before new growth begins." It advises spring for dogwoods, magnolias, willow oaks, tulip poplar and yellowwood, which have fleshy roots. Broadleaf evergreens go in spring too, though it allows mountain laurel and hollies an early fall move if they are watered and mulched. Iowa State University Extension writes: "Early spring is generally the best time to transplant; conditions should be ideal for rapid root growth." It moves an evergreen in early spring or from late August to mid September, and a hardwood once it is dormant. The Morton Arboretum gives spring to bald cypress, American hornbeam, larch, magnolia, hemlock, sweetgum, tuliptree, willow, broad-leaved evergreens and yews. It names alder, ash, buckeye, catalpa, crabapple, hackberry, hawthorn, elm, linden, maple, pines and spruces among the trees that take a fall move. It finds November and December late, and allows six weeks before the ground freezes. University of Minnesota Extension says: "Do not plant evergreens later than October so the roots will have a chance to become established." No source gives a leaf-out month for each species, so the spring window ends at the tree's own bud break.

The Morton Arboretum says: "Research has shown that approximately one year of recovery is needed for every inch of tree diameter." A red oak trial at Ohio State University, published in 2000, found 1.5-inch trees established in 3 years in zone 5, which its authors call consistent with a year per inch. The other climates come from the sources the site's article on small saplings cites. Virginia Tech's Tree Steward Manual gives six months per inch in zones 7 and 8, read from the Internet Archive's copy of 2026-03-14. UF/IFAS Extension tables Florida by trunk size: "For each additional inch of trunk diameter, trees in north Florida require 4 months for establishment. Trees in central and south Florida require 3 months." University of Minnesota Extension gives a year and a half per inch, the watering calculator's figure. It gives a shrub at least two growing seasons, until its roots spread as wide as its top.

The small sapling beside the moved tree follows Gary Watson's model in the International Society of Arboriculture's Journal of Arboriculture, 1985: "The larger tree grows very slowly for many years, while the smaller tree resumes a normal rate after only a few years." In the Ohio State trial the large red oaks that lived kept their lead for four years, though 7 of 12 died.

It is a starting point, not a promise. The whole move, from timing to the first summers, is in Transplanting young trees: timing, water and protection. Why the seedling so often wins is in Why a small sapling catches up with a big transplanted tree.