Northern Catalpa

Taxobox
name = "Catalpa speciosa"

---

image_width = 240px
image_caption =
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
ordo = Lamiales
familia = Bignoniaceae
genus = "Catalpa"
species = "C. speciosa"
binomial = "Catalpa speciosa"
binomial_authority = (Warder) Warder ex Engelm.

Northern Catalpa ("Catalpa speciosa") is a species of "Catalpa", native to the midwestern United States in Arkansas, Illinois, Indiana, Missouri, KentuckyPennsylvania, and Tennessee.

It is a medium-sized deciduous tree growing to 15-30 meters tall. It has a trunk up to 1 m diameter with brown to gray bark, maturing into hard plates or ridges. The leaves are large, heart shaped, 20-30 cm long and 15-20 cm broad. The flowers are 3-6 cm across, trumpet shaped, white with yellow stripes and purple spots inside; they grow in panicles of 10-30. The catalpa tree is the last tree to grow leaves in the spring. The leaves generally do not color in autumn before falling, instead, they either fall abruptly after the first hard freeze, or turn a slightly yellow-brown before dropping off.

The fruit is a long, thin bean like pod 20-40 cm long and 10-12 mm diameter; it often stays attached to tree during winter (and can be mistaken for brown icicles). The pod contains numerous flat light brown seeds with two papery wings.

It is closely related to Southern Catalpa, and can be distinguished by the flowering panicles, which bear a smaller number of larger flowers, and the slightly broader seed pods.

Cultivation and uses

It is widely grown as an ornamental tree. It prefers moist, high pH soil and full sun but has been able to grow almost anywhere in North America, and has become widely naturalized east of the Rocky Mountains outside of its restricted native range.

The wood is soft like white pine and light, weighing only 26 pounds per cubic foot when dry. It also does not rot easily; in earlier years it was used for fence posts and less than successfully as railroad ties. More modern usage that highlight the wood's beautiful grain includes furniture, interior trim and cabinetry. Surprisingly catalpa has the lowest shrinkage/expansion rate of any domestic (USA) hardwood. Only northern white cedar and redwood have lower shrinkage/expansion rates and not by much. The wood's unique properties make it excellent for carving and boatbuilding. Often regarded as a weed tree its wood is under appreciated and under utilized. The tree's tendency to grow crooked does not help its reputation as a source of usable lumber.

References

* [http://plants.usda.gov/java/profile?symbol=CASP8 USDA Plants Profile: "Catalpa speciosa"]
* [http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?9592 Germplasm Resources Information Network: "Catalpa speciosa"]