Introduction
This hawthorn grows asymmetrically 20 to 30 feet tall and spreads 10 to 25 feet. The tree has lustrous foliage and fewer thorns than some other hawthorns. The flowers are white, large, and borne in spring. The fruit are borne in bright orange-red clusters and they are marked with brown and persist until spring. The fall color is bronze red. It is an all-around attractive tree providing interest throughout the year.
General Information
Scientific name: Crataegus x lavallei
Pronunciation: kruh-TEE-gus x luh-VALE-ee-eye
Common name(s): Lavalle hawthorn
Family: Rosaceae
USDA hardiness zones: 4A through 8A (Figure 2)
Origin: not native to North America
Invasive potential: not assessed/incomplete assessment
Uses: street without sidewalk; tree lawn 3–4 feet wide; tree lawn 4–46 feet wide; tree lawn > 6 ft wide; highway median; bonsai; specimen
Description
Height: 20 to 30 feet
Spread: 15 to 25 feet
Crown uniformity: irregular
Crown shape: vase, oval
Crown density: moderate
Growth rate: moderate
Texture: medium
Foliage
Leaf arrangement: alternate (Figure 3)
Leaf type: simple
Leaf margin: serrate
Leaf shape: elliptic (oval), oblong
Leaf venation: pinnate
Leaf type and persistence: deciduous
Leaf blade length: 2 to 4 inches
Leaf color: green
Fall color: no color change
Fall characteristic: not showy
Flower
Flower color: white/cream/gray
Flower characteristics: showy
Fruit
Fruit shape: round
Fruit length: 0.5 to 1 inch
Fruit covering: fleshy
Fruit color: orange, red
Fruit characteristics: does not attract wildlife; showy; fruit/leaves not a litter problem
Trunk and Branches
Trunk/bark/branches: branches droop; not showy; typically one trunk; no thorns
Pruning requirement: little required
Breakage: resistant
Current year twig color: green
Current year twig thickness: medium
Wood specific gravity: unknown
Culture
Light requirement: full sun
Soil tolerances: clay; sand; loam; alkaline; acidic; well-drained
Drought tolerance: high
Aerosol salt tolerance: low
Other
Roots: not a problem
Winter interest: yes
Outstanding tree: no
Ozone sensitivity: unknown
Verticillium wilt susceptibility: resistant
Pest resistance: sensitive to pests/diseases
Use and Management
The tree is used extensively as a street tree in some areas of the country because they are tough. It is an excellent garden shrub border plant, providing a refreshing white bloom in spring, fall color, and attractive fruit. Specify tree-form when planting along the street.
Pests
Aphids can be partially controlled with strong sprays of water from a garden hose, if the colony is in the lower branches. Sometimes the aphids themselves are not seen but the distorted growth, honeydew on the leaves, and sooty mold growing on the honeydew are obvious.
Borer attacks may be prevented if the trees are kept in good vigor with regular fertilization.
Leaf miners symptoms are brown blotches on the leaves.
Lace bugs can be a serious, though occasional, problem. The insect feeding on the undersides of the leaves causes chlorotic flecks on the upper leaf surfaces. The lower sides of the leaves are covered with small, brown, sticky flecks.
The pear slug skeletonizes hawthorn leaves and these sawfly larvae have a slimy appearance. A few insects can be washed off with a garden hose.
Tent caterpillar nests can be pruned out while still small. Sprays of Bacillus thuringiensis may be used. Do not burn nests while the nests are in the tree. The injury from the fire may exceed that caused by the insects.
Overwintering scales can usually be controlled with horticultural oil sprays.
Spider mites are so small they can cause much foliage discoloration before being detected.
Diseases
Fire blight, this disease can be severe in some parts of the country. The first noticeable symptom of fire blight is the browning of branch tips. The tips appear to be burned or scorched and the dead, brown leaves droop but hang on the tree. Cankers form and the bacteria is washed farther down the branch by rain. The bacteria are spread from diseased to healthy twigs by bees and contaminated pruning tools. There is no satisfactory chemical control. The disease is less of a problem if trees are not located near apple or pear orchards. Prune out blighted branch tips by cutting a foot or two beyond the diseased wood. Over-fertilizing with nitrogen fertilizer may increase tree susceptibility to fire blight.
Leaf blight attacks most hawthorns but especially English hawthorn. The symptoms are small reddish-brown spots on the leaves which may run together. Infected leaves drop in August and severely infected trees may be completely bare.
Cedar hawthorn rust causes orange or rust colored spots on the leaves leading to early defoliation. The fruits and twigs are also attacked. Juniper is an alternate host. Cedar-quince rust attacks fruits. Washington, Lavelle, and cockspur hawthorn are resistant to rust diseases.
Scab causes leaf spotting and defoliation. The fruit have black raised spots on them.
Powdery mildew causes a white powdery growth on the leaves.
