Juglans nigra - Black walnut
Black walnuts are very tall, statuesque, shade trees best planted in informal settings. Their wood is prized for furniture building and over-harvesting has caused a serious decline in native populations. They are host plants for over 100 species of butterflies and moths! Plant this tree in full sun where it will have room to grow and falling nuts will not be a problem. They prefer full sun and moist, well-drained soil.
- Host plant for over 100 butterfly and moth species!
- The insects attract a wide array of birds
- Over-harvesting has caused a decline in native populations
- The preferred host plant of the luna moth
- Important food source for squirrels and chipmunks
Native to rich, moist woods and bottomlands.
Map Credit: The Biota of North America
Map Key: Green (native), Teal (native, adventive), Blue (present), Yellow (present & rare), Red (extinct)
Some walnuts will start producing nuts when they are 5 or 6 years old. However, you may need to wait 15 years or more for a heavy crop.
Black walnuts produce chemicals called juglones which are very toxic to certain other plants such as azaleas, rhododendrons, blueberries, peonies, and solanaceous crops like tomatoes, peppers, and potatoes. Most of the toxicity is limited to within the drip line of the tree.