Photo: Robert H. Mohlenbrock, USDA NRCS, Public domain · Wikimedia Commons
Shellbark Hickory (Kingnut)
Carya laciniosa
Also called kingnut, big shellbark, bottom shellbark, thick shellbark, western shellbark, bigleaf shagbark hickory.
The largest hickory nut, sweet and thick shelled, on a shaggy-barked tree of river bottoms that stands spring floods; rare in the wild and rarer in nurseries.
EdibleWildlife valueTolerates wet soilFall colorRare
- Type
- Large tree
- Mature height
- 60–80 ft
- USDA zones
- 5–8
- Growth rate
- Slow
- Sun
- Full · Part
- Soil moisture
- Average · Wet
210
Shellbark hickory is the bottomland cousin of shagbark, a tree of deep, moist, fertile river terraces that stand a few weeks of shallow flooding in spring. Its heart is the lower Ohio valley and the Mississippi down to Arkansas, thinning east through Pennsylvania; it reaches Maryland along the Potomac, where the state lists it as endangered; Virginia has no wild trees on record. It is a shagbark with everything bigger: seven leaflets to shagbark's five, orange-brown twigs, bark in long plates that peel a little less and the largest nut of any hickory, egg shaped with a sweet kernel inside a very thick husk that splits in four in fall. Squirrels and chipmunks plant the nuts; deer, foxes, raccoons, black bears, wild turkeys, ducks and quail eat them; the regal moth's hickory horned devil feeds on the leaves. Ideal for a floodplain field, a creek terrace or a low corner of a big lawn where a pecan would also grow.
It is rare for a plain reason: a seedling bears nothing until about 40 years old and the nuts are too heavy to travel far, so it never came back to cleared bottoms; nurseries skip it because the taproot makes it hard to move. It is very shade tolerant when young, sprouts from the stump after damage and crosses with shagbark and pecan; a second shellbark nearby gives a bigger crop of better nuts.
How to grow Shellbark Hickory
Shellbark hickory is hardy in zones 5 through 8 and wants full sun or part shade on deep, moist, fertile loam; it takes a few weeks of shallow flooding in spring and does poorly on heavy clay or a dry ridge. It grows 60 to 80 feet tall and 40 to 60 wide, so give it 30 feet from the house and off the drive, where the nuts drop.
Plant a dormant sapling from leaf fall until bud swell, in a hole deep enough for the taproot to hang straight and wider than the rest, flare at grade, native soil back in, mulch off the trunk. Sow nuts in fall an inch deep under hardware cloth, or squirrels dig them, or soak them a few days, hold them damp in the refrigerator for 90 to 120 days and sow in spring; they come up in late spring. Seedlings like light shade the first summer and put their first year into the taproot.
Water weekly through the first summer if rain is short. Deer browse the leaves and rabbits gnaw hickory bark, so tube the stem for three years and keep mulch thin at the base against voles. Prune in the dormant season only to keep one leader; hard cutting brings water sprouts, and twig girdlers may clip the tops of young trees.
Growth is slow; seedling trees bear at about 40 years and then a good crop about every second year, two or three bushels from a thriving tree. Male and female flowers share a tree, opening after the leaves in April and May; a second shellbark nearby gives a bigger crop of better nuts. Late frost nips new growth. Weevils and shuckworm take some of the crop and drought invites the hickory bark beetle; no disease threatens it.
Heights and zones are typical ranges for the species in cultivation; local conditions and seed source shift them.
- Six trees not to plant near a house, and what to plant instead
- Pruning at the branch collar, and when to make the cut
- Native trees and shrubs for butterflies and moths: host plants first, nectar second
- Native trees and shrubs for wildlife: what deer, squirrels, bears, bats and turtles get from a planting
- Ten planting mistakes that quietly kill trees
More like this
