Black Walnut Juglans Nigra

Pruning Juglans nigra

Juglans nigra should be trained with a clear stem as this will accommodate for the slightly weeping branches. It should have a natural central leader, however dual leaders might develop. Remove competing leaders as soon as possible, either as a bud or young shoot.

Juglans do not respond well to hard pruning, and pruning of established trees should be kept to a minimum. If you do need to remove established branches, the branch collar needs to be kept.

What time of year should I prune? Late summer through to early winter. The sap rises early so pruning in late winter will result in bleeding. 

For the continued healthy growth of your trees, shrubs or hedging it is vital that you follow the advice below.

Watering

The main reason that plants die within 12 months of having been planted is lack of water. It is essential throughout the spring and summer, to give a heavy enough watering to enable the water to penetrate right down to the deepest root level of the tree. In hot dry spells give the equivalent of 2 bucketfuls every three days.

Weed Control

One of the most common causes of lack of water is competition from grass. When trees are first establishing, the grass roots would be at the same level as the tree roots and are far more efficient at taking up water and thus choke the tree. It is vital that for at least 3 years after planting your tree or hedge has a circle or strip one metre wide completely free of grass.

1. Mulch mats are an effective way to stop grass and weeds, although they will require a careful eye to make sure they continue to work. After clearing the ground around the tree, firmly fit the mat by tucking the edges into the soil and put a thick layer of bark mulch on top of this. Be careful not to allow the woodchip to touch the stem as it can cause rot.
2. Weed killer is very effective, however it is harmful to the environment. Organic weed killers usually do not kill roots. Weed killer needs to be applied each year for the first 3 years, preferably when the tree is dormant, or just once before applying a mulch mat.
3. Mowing or strimming is NOT an answer to the problem. Each time you mow, the grass will grow back more vigorously and strimming invariably leads to lacerated trunks.

Staking

If trees are not correctly secured they will rock in the planting pit. Roots not firmly in contact with the soil are unable to take up moisture and nutrients, resulting in die back or death of the tree. Check, particularly after windy weather, that stakes are still solidly in the ground keeping the base of the trunk firm. The purpose of the stakes is to anchor the roots. Flexing in the wind, higher up the trunk, is not necessarily a problem if the roots are firm.

Bellow is list of the correct system to use to secure your trees.

• 40/60, 60/80, 80/100 whips - Unless rabbit/deer problem no need to stake.
• 100/125, 125/150 1.2m Cane and Easi tie.
• 150/175 1.2m square stake and a buckle tie and spacer.
• 175/250, 6/8, 8/10 15L 1.65 Tree stake and a buckle tie and spacer.
• All larger trees. 2 x 1.65 Tree stake and cross rail with 38mm cushion spacer and 1m of 38mm strapping.

Ties

Always use our recommended tree ties or strapping. These are designed and manufactured with the correct amount of give to hold the tree firm without strangling it. They should be checked at the end of each growing season for adjustment as the trunk thickens. Non proprietary materials such as baler twine will cut into the bark and should not be used.

Protection from Animal Damage

Rabbits, deer, sheep, cattle and horses can all potentially damage trees. Ask us for advice on the most appropriate guards for your trees or hedge. Squirrels are also a terrible pest when trees get to about 20ft tall but there is no protection available.