Tilia americana 'Fastigiata': 'Fastigiata' American Linden

Introduction

'Fastigiata' American linden grows 50 to 70 feet tall and 30 to 45 feet wide forming a narrow pyramidal shape with upright branches and shiny leaves and is fairly drought tolerant. The tree is pyramidal when young but develops into a striking specimen with an upright, rounded oval atop a tall, straight trunk. The lower branches remain on the tree and gently drape toward the ground before sweeping up in a gentle curve. The four to eight-inch-long, heart-shaped leaves are dark green throughout the year fading only to pale green or yellow before dropping in autumn. In June, the trees produce abundant, two to three-inch-wide clusters of very fragrant, light-yellow blooms which are extremely attractive to bees, who make a delicious honey from their harvests. The small, grey nut which is later produced will persist on the tree until midwinter. The trunk on the species can grow to six feet or more across on mature specimens.

General Information

Scientific name: Tilia americana

Pronunciation: TILL-ee-uh uh-mair-ih-KAY-nuh

Common name(s): 'Fastigiata' American linden, 'Fastigiata' basswood, 'Fastigiata' American basswood

Family: Tiliaceae

USDA hardiness zones: 4A through 8B (Figure 2)

Origin: native to North America

Invasive potential: native cultivar

Uses: hedge; street without sidewalk; tree lawn > 6 ft wide

Description

Height: 50 to 70 feet

Spread: 30 to 40 feet

Crown uniformity: symmetrical

Crown shape: pyramidal, columnar

Crown density: dense

Growth rate: moderate

Texture: coarse

Foliage

Leaf arrangement: alternate (Figure 3)

Leaf type: simple

Leaf margin: serrate

Leaf shape: ovate, cordate

Leaf venation: pinnate

Leaf type and persistence: deciduous

Leaf blade length: 4 to 8 inches

Leaf color: green

Fall color: yellow

Fall characteristic: not showy

Flower

Flower color: yellow, green

Flower characteristics: showy

Fruit

Fruit shape: round, oval

Fruit length: less than 0.5 inch

Fruit covering: dry or hard

Fruit color: tan

Fruit characteristics: does not attract wildlife; not showy; fruit/leaves not a litter problem

Trunk and Branches

Trunk/bark/branches: branches don't droop; not showy; typically one trunk; thorns

Pruning requirement: little required

Breakage: susceptible to breakage

Current year twig color: green, brown

Current year twig thickness: medium

Wood specific gravity: 0.37

Culture

Light requirement: full sun, partial sun, or partial shade

Soil tolerances: clay; sand; loam; slightly alkaline; acidic; well-drained

Drought tolerance: moderate

Aerosol salt tolerance: none

Other

Roots: not a problem

Winter interest: no

Outstanding tree: no

Ozone sensitivity: unknown

Verticillium wilt susceptibility: resistant

Pest resistance: resistant to pests/diseases

Use and Management

This tree is large and needs plenty of room to develop. Branches should be well-spaced along a central trunk to allow for development of a durable structure. Left unpruned, crotches with embedded bark can develop but the wood is flexible, so branches usually do not break from the tree. The tree is considered to have a strong branch structure. Plant it as a specimen or shade tree on a commercial property where there is plenty of soil space available for root expansion. It can be used as a street tree in large tree lawns or along a street without a sidewalk but is sensitive to road salt. Be prepared to remove sprouts periodically from the base of the trunk.

A North American native tree, American linden prefers moist, fertile soils, acid or slightly alkaline, in full sun or partial shade. More shade tolerant than many other large trees. The leaves will show appreciable browning after a particularly dry season, but the tree appears fine the following year. It is often found (and prefers) growing along moist stream banks but tolerates some drought.

The cultivar 'Legend' is pyramidal, grows with a single, straight trunk, and upright, well-spaced branches; 'Redmond' has a broad pyramidal canopy. These can all be used in large tree lawns along streets.

Propagation is by seed, cuttings, or grafting.

Pests

Mainly aphids, although Japanese beetle, European linden bark borer, linden borer, walnut lace bug, caterpillars, basswood leaf miner, elm sawfly, scales, and linden mite can all be troublesome problems. The aphids will secrete a honeydew which will result in a dark soot over objects below the tree, such as parked cars or lawn furniture.

Diseases

Anthracnose, leaf blight, canker, leaf spots, powdery mildew, and verticillium wilt are some diseases than can infect American linden. Leaf rust can cause some defoliation.