NORTH AMERICAN ANGIOSPERMS
Our 17 chosen angiosperm families contain 32 significant genera, listed below by family:
Salicaceae - the willow family
Though containing only two genera, Salicaceae is TOTALLY species rich (mainly in shrubs) thanks to its namesake genus Salix. Most member species in this family grow in 'riparian' (i.e., streamside) ecosystems in temperate/boreal forests in the northern hemisphere. They therefore are well adapted to flooding disturbances, regenerate via both sprouting (following damage) and water-disseminated seed, grow rapidly once established, and are generally very intolerant to shade.
(400 species globally, 80 in North America)
Populus -- poplars (35 species globally, 10 in North America)
Betulaceae - birch family
Five genera in the birch family contain significant North American tree species and shrubs, but we will cover species in only two of them. The other three (Carpinus, Ostrya, and Corylus) are of only minor importance in the eastern deciduous forests. Like Salicaceae, species in the Betulaceae family are fast growing, riparian, moist- site trees.
species globally, 18 in North America)
species globally, 8 in North America)
- beech/oak family
This family, because of the genus Quercus, is one of the MOST significant of the angiosperms in terms of ecological amplitude and richness, ecosystem importance and commercial value. Though named for the genus Fagus, Quercus is the 400 lb. gorilla on this bus!
only 1 in North America)
chestnut (10 species globally,
only 1 tree species in North America)
golden chinkapin (only 2 species globally,
both in North America)
Notholithocarpus -- tanoak (1 species globally)
- walnut family
This family is not particularly large but very important given the value of it nuts (for wildlife and humans) and, particularly for Juglans, its timber. This is also our first family with compound leaves - leaves that are comprised on a collection of 'leaflets.'
walnut (20 species globally,
6 in North America)
hickory (18 species globally,
13 in North America)
Ulmaceae - elm family
Ulmaceae is a large and important family globally (18 genera), but we North Americans only have 2 genera with significant tree species. Many of the species in this family are well known for their ornamental and landscaping value, but they also form an important part of the species mix in eastern deciduous forests.
elm (20 species globally,
6 in North America)
hackberry (60 species globally,
6 in North America)
- magnolia family
Magnoliaceae is an ancient family with a long fossil record...and some really unusual features like its large flowers. It is the name sake for the Order Magnoliidae and Class Magnoliopsida - the 'dicots' that include ALL the angiosperm trees for this course.
magnolia (120 species globally,
but only 8 in North America)
yellow-poplar (only 2 species globally,
1 of which is native to North America)
Platanaceae - sycamore family
This is a small family, with just the one genus and 6-7 species. Sycamore is important riparian tree and a common landscaping species.
Platanus -- sycamore (6-7 species globally, 3 in North America)
Rosaceae - rose family
The rose family is one of the biggest and MOST diverse of the angiosperms with nearly 100 genera and 3000 species. Most of these are beautiful, flowering herbs, vines, and shrubs, but foresters work with about 10 genera that have tree form species that have important economic or ecological value. We will cover six.
cherry (200 species
globally; 30 in North America, 18 tree species, but only one common forest tree)
serviceberry (33 species globally,
10 in North America)
hawthorn (>100 species globally,
probably 35 in North America)
apple (55 species globally,
probably 5 in North America)
pear (20 species globally,
a few in North America)
Sorbus -- mountain-ash (100 species globally, 4 in North America)
Hamamelidaceae - witch-hazel family
This is a moderately sized family with about 31 genera but only 100 species, and many are shrubby rather than tree form. We are interested in only one tree species in the entire family.
or 4 species globally, and only 1 in North America)
Tiliaceae - linden or basswood
Tiliaceae is a good sized family with 50 genera 680 species, which are particularly abundant in the southern hemisphere. The Europeans use the common name "linden" but "basswood" is more commonly used in the States. We are concerned with one genus.
Tilia -- basswood (45 species globally, as many as 20 in North America)
Caesalpiniaceae - Caesalpinia family
This is another huge family, 153 genera and 2175 species, dominated by shrubs, lianas (vines) and herbs. I was impressed by the number of references to Caesalpiniaceae while I was in the tropics (Mexico and Honduras). Only seven of the genera have tree form species, and we are interested in only one tree species in this extensive family.
honeylocust (14 species globally,
only 2 in North America)
Fabaceae - pea or bean family
Fabaceae is the granddaddy of the angiosperm family with 425 genera 12,150 species, 14-times more than all gymnosperms combined; of course, the vast majority are not trees. Only eleven species from 8 genera reach tree size in the States, and we are concerned with one of them: Robinia. Members of Fabaceae and Caesalpiniaceae are considered "legumes", like the green beans from the garden, which means their fruits look like beans and they support symbiotic bacteria-like organisms that "fix" atmospheric nitrogen into plant-useful forms.
locust (4 species globally,
all in North America)
Bignoniaceae – trumpet-creeper family
This is another large family, also more common to the tropics, with 109 genera and about 750 species. Only four genera contain tree size species in North America, and we are interested in only one genera.
catalpa (11 species globally,
2 in North America)
Aceraceae - maple family
Aceraceae is contains only 2 genera but 113 species, most of which are in the one genus Acer (its namesake) discussed in detail at the genus level because of its value to forestry in North America. This is the first family in this course that has an "opposite arrangement" - it's leaves emerge from twigs directly opposite each other (check it out on the CD). I learned an acronym pneumonic to help remember this identification key: "MAD Horse", for maple, ash, dogwood and horsechestnut...all with opposite arrangement and the last four families!
maple (110 species globally,
14 in North America)
- olive/ash family
This is a moderate sized family, with 24 genera and 615 species, with most species originating in the northern hemisphere. Only four genera contain tree size species in North America, and only one is significant to forest management.
ash (65 species globally,
16 in North America)
Cornaceae - dogwood family
The dogwood family is rather small but taxonomically complex, with 14 genera and about 120 species. Cornus is particularly well known for its distinctive flowers (trees, shrubs and herbs); Nyssa is a recent taxonomic addition to this family.
(65 species globally, 16 in North America)
(7 species globally, 4 in North America)
Hippocastanaceae - buckeye family
This is a small family of only 2 genera and 15 species. Though named the 'buckeye' family, another common name is "horsechestnut" given its chestnut-like fruits. That may help you remember the Latin name for the family, as well as the "MAD Horse" pneumonic. Only one genus is really significant.
or horsechestnut (13 species globally, only 2 tree species in North America)
Angiosperm SPECIES LIST
Angiosperm EXAM STUDY GUIDE