As agriculture is Pennsylvania's leading industry and trees are Carbon County's leading industrial product, Kevin and Patti Borger, who jointly own and operate the Borger Farm tree nursery in Lehighton, are proud to be tree-huggers.

Having managed their tree farm for 20 years, the Borgers are working twice as hard this year just to stay were they would be in any normal year.

"The normal digging season is the second week of March to the second week of May," Kevin said. "This year we started digging the end of March and it will probably end sometime in April." Kevin and Patti planted their last saplings on April 15.

"There was a lot of moisture in the ground and it got warm," Kevin explained. "The trees have a cycle based on growing degree days, an average of the maximum and minimum temperatures."

With warm weather followed by snow, the trees budded early while the ground remained cold.

It's important to transplant saplings before the buds become leaves, especially for deciduous trees.

Once the leaves open, the leaves are susceptible to moisture loss, a stress to the tree.

Since the second week in March, the Borgers have been transplanting broad-leafed varieties such as Red Bud, oak, maple, flowering pear, sweet gum, birch and zelcova.

For the remainder of April, they may continue planting conifers such as Douglas Fir, Fraser Fir, Blue Spruce, and White Pine.

Much of the stock they plant is grafted.

Typically, durable root stock is grown the first year, then a graft of the desired stock is made, and the grafted tree is allowed to mature for a second year before it is ready for transplanting.

While Pennsylvania has ideal growing conditions for hardy trees, its short growing season makes farming of starter stock difficult.

Realizing this, the Borgers have developed suppliers in Tennessee, West Virginia and Oregon.

These nurseries are able to dig their stock early in the year and get them to the Northeast in time for Pennsylvania's planting season

This stock comes to the Borgers as a whip, a sapling that is about as thick as a thumb. Conifers run seven to 10 feet tall, and deciduous trees a bit smaller at six to eight feet tall. The whip stock either has no branches or small branches.

The whips are shipped in special air root pruning containers.

Where conventional plastic containers tend to force the roots into a circular cluster, the air root pruning containers are vented so that when the roots contact air, they turn downward.

Kevin said that while perhaps 50 percent of the roots of small stock are damaged transplanting from conventional containers or balled and bagged stock, the air root pruning container "does not damage the roots of the tree and there is little transplant shock."

Kevin and Patti grew up locally, Kevin in Ashfield, Carbon County, and Patti in West Penn Township, Schuylkill County. They wanted to marry and start a tree farm together.

They found a tomato and egg farm for sale in Lehighton. Between the land they own and lease, they have 68-acres available for growing trees.

While allowing their stock to grow, the Borgers sold cut Christmas trees in season.

"We expanded our farm with full knowledge that we would become a nursery not just a cut tree farm," noted Patti. "We would dig trees for the nursery and landscape industries so that our live trees would be going into the ground. We still sell wholesale Christmas trees but our major market is the landscape industry with a full line of shade trees, deciduous trees, and conifers."

Besides the short planting season, Patti sees 2010 as a difficult year for the landscaping industry.

"The tree industry follows the building industry which is in a down economy. People have less discretionary money and are cutting back," she explained. "Other states are also supplying Pennsylvania nurseries with trees."

If you are thinking about tree planting this spring, their advice is to hurry since the leaves are budding. Spring has sprung.

If you are transplanting a tree, here's Kevin and Patti's recommendations:

1. Select a location with good water drainage.

2. Dig a hole about two inches wider than the ball and at a depth so that the trunk soil lines match or the transplant is no more than an inch above.

3. Backfill with the dirt removed. Do not add anything to the soil.

4. Protect the truck for the first three years with a tree guard to prevent male deer from rubbing his antlers and scrapping the bark off the tree. Hang deodorant soap from the tree branches to prevent the deer from browsing the shoots.

5. Water the tree if you don't get an inch of rain every two weeks. Water every week in hot weather, give a soaking.

6. In the spring of the second year, along the drip edge of the tree, fertilize with a balanced fertilizer.