Time to remove fallen leaves, buckthorn trees

After a killing frost, remove dead plant debris from annual and vegetable beds.

Sanitation is especially important if you have had disease problems in your planting beds. Remove all diseased foliage or fruits and do not add affected materials to your compost pile, because most home compost piles do not get hot enough to kill disease organisms.

• Buckthorn is an invasive tree and common throughout the Chicago area. It tends to hold green leaves later than other deciduous trees in fall so it is easy to spot.

Cut buckthorn at ground level and quickly treat the stump with an herbicide to kill the root system. Smaller trees can be dug out with a sharp spade.

• Shredded leaves make good mulch for your garden beds. For the serious gardener, a shredder can be rented but be aware that they are very noisy, so it is best to use ear and eye protection when using.

A shredder can be a time-consuming process but results in a finer leaf mulch. For the average gardener, a lawn mower with a bag to catch the leaves will be adequate. The mower doesn't cut the leaves up as finely as a shredder but works a lot faster.

Ground-up leaves will also decompose more quickly if you are using them in a compost pile. Shredded leaf mulch can also be purchased from garden centers.

• In most garden situations, tree wrap is not needed for newly planted trees. If used, it should be removed within six months to a year at most.

Tree wrap is used in certain areas of the Chicago Botanic Garden to help prevent animal damage in winter. These trees are wrapped in October and November and the wrap is removed in April. Both paper and burlap tree wrap work well.

When using paper tree wrap, place the printed side against the trunk so it cannot be seen when wrapping is completed. Start the wrap at the bottom of the trunk and finish at the top.

• Tim Johnson is director of horticulture at Chicago Botanic Garden, chicagobotanic.org.