New Jersey Plants--Fifteen Big Families

Compiled by Karl Anderson, used with permission
The following fifteen plant families contain a total of 1,491 species, or about 50% of the roughly 3,000 plants known to be "growing without cultivation" in New Jersey today. Numbers are from a Check List of the Plants of New Jersey--1999 (unpublished) by Karl Anderson.

  1. Composite Family (Asteraceae) - Dicot plants, mostly herbaceous, rarely shrubs. Flowers in heads, often showy, usually containing many flowers. Flowers of two types: either regular "disc" flowers or strap-shaped "ray" flowers. Flowers may be perfect or imperfect or neuter, and depending on the species, the flowers in a head may be all regular, or all strap-shaped, or with central flowers regular and the peripheral (ray) flowers strap-shaped. 291 species in New Jersey (192 native), in 74 genera, including Aster (aster), Bidens (beggar-ticks), and Solidago and Euthamia (goldenrods). A fairly easy family to recognize; if it looks like a daisy, a dandelion, or a thistle it's probably a composite.
  2. Sedge Family (Cyperaceae) - Mostly perennial herbaceous monocots, superficially grass-like, most abundant and divers in wet habitats. Stems are usually solid, without joints, and often (but not always) triangular in cross-section. Leaves (if present) are three-ranked, with sheath and blade but no ligule. Flowers are tiny, usually imperfect, and wind pollinated. In Carex, female flowers are enclosed in a sac-like perigynium. Flowers grow in spikes or spikelets, with 6 hair-like sepals or none; no petals, 3 stamens, 1 pistil. 265 New Jersey species (257 native), in 13 genera, including Carex (the "typical" sedges; about 158 species), Cyperus (umbrella-sedge), Eleocharis (spike-rush), Rhynchospora (beaked-rush), and Scirpus and Schoenoplectus (bulrush), a difficult group, with no popular literature. Identify the family by the 3-ranked leaves and usually triangular stem; species by usually minute details of flower, perigynium, and achene.
  3. Grass Family (Poaceae) - Annual or perennial herbaceous monocots, with stems usually round in cross section and hollow except at the joints, or nodes, at which the leaves are attached. Leaves are 2-ranked, alternate, and consist of three parts: sheath, blade, and ligule. Flowers are tiny, enclosed between bracts (lemma and palea); growing in a variety of spikes, spikelets, and panicles, with 2 or 3 very small sepals, no petals, 3 or 6 stamens, 1 pistil. 269 species in New Jersey (177 native), in 89 genera, including Agrostis (bent-grass), Bromus (broom-grass), Festuca (fescue), Spartina (cord-grass), Panicum (panic grass), and Dicanthelium (rosette grass).
  4. Rose Family (Rosaceae) - Dicot herbs, shrubs, vines, and trees, usually with alternate, stipulate, simple or compound leaves. Flower parts, other than pistils, arise from a disc- or cup-shaped receptacle or hypanthium. Flower color and arrangement various (but not blue); with 5 sepals, 5 petals, many stamens, and 1 to many pistils. Fruits various. 113 New Jersey species (85 native), in 21 genera, including Rose (Rose), Prunus (cherry, peach, and plum), Malus (apple), Crataegus (thorn), Potentilla (cinquefoil), and Rubus (blackberry). Identify the family by the five-parted flowers with a receptacle and many stamens.
  5. Legume Family (Fabaceae) - Dicot herbs, shrubs, or sometimes trees with alternate and usually compound stipulate leaves. Flowers irregular, variously colored, in racemes, panicles, or heads, with 5 sepals, 5 petals, of which on (the "standard") is larger than the rest, while two others form a boat-shaped structure enclosing the sexual parts of the flower; 10 stamens, usually in two sets, of 9 and 1, and 1 pistil. Fruit a pod containing 1 to many seeds and splitting along the edges. 113 New Jersey species (55 of them native), in 41 genera, including Robinia (locust), Trifolium (clover), Vicia (vetch), Desmodium (tick-trefoil) and Lespedeza (bush-clover). Identify the family by the characteristic flowers, seed pods, and compound leaves.
  6. Mint Family (Lamiaceae) - Annual or perennial dicot herbs, sometimes aromatic, with opposite, usually simple leaves and usually 4 sided stems. Flowers irregular, in spikes or axillary clusters, or both, with 5 united sepals, 5 petals, united into a tube which is often strikingly two-lipped; 2 or 4 stamens (if 4, in two sets of 2); and 1 2-parted pistil. Fruit with 4 nutlets enclosed in a persistent calyx. 80 New Jersey species (41 native) in 32 genera, including Mentha (mint), Scutellaria (skullcap), Nepeta (catnip), Monarda (bee balm), and Lamium (dead-nettle). Identify the family by the square stem, opposite branching, irregular 2 lipped flowers, and sometimes by aromatic foliage; species by flower color, leaf shape, and details of flower.
  7. Mustard Family (Brassicaceae) - Herbaceous dicots with acrid, watery sap; alternate leaves, and often a basal rosette. Flowers usually in racemes; regular; variously colored, though white and yellow are commonest; with 4 sepals, 4 petals, 6 stamens in two groups of 4 and 2; and one 2-parted pistil. Fruit is a silique--a dry pod-like fruit having an internal partition which remains on the plant after the fruit splits and releases the seeds. One of the most-easily recognized families; look for the 4-merous flowers and silique fruits. 69 New Jersey species (23 of them native) in 36 genera, including Brassica (mustard), Barbarea (winter cress), Cardamine (bitter cress and toothwort), and Arabis (rock cress).
  8. Snapdragon Family (Scrophulariaceae) - Dicots, mostly herbs, with various leaf arrangements. Flowers complete, usually irregular, arranged in spikes or racemes; with 4 or 5 united sepals; 4 or 5 petals, often united into a tube which is two-lipped; usually 4 stamens (sometimes 2 or 5); and one 2-parted pistil. Fruit a capsule or berry. 63 New Jersey species (41 native) in 26 genera, including Verbascum (mullein), Veronica (speedwell), Agalinis (gerardia), and Penstemon (beardtongue). Identify the family by the irregular flowers; distinguish from mints by fruit, lack of aromatic foliage (usually), and usually round stem.
  9. Orchid Family (Orchidaceae) - Perennial monocot herb. Flowers strikingly irregular; sometimes very showy; ovary beneath the flower; with 3 sepals (usually alike), 3 petals, one very different from the other 2; 1 pistil. Fruit a capsule, seeds very numerous, almost microscopic, needing penetration by specific soil fungi to develop. A very large plant family, with over 20,000 species world-wide, mostly tropical. New Jersey has 54 species (53 native), in 19 genera, including Corallorhiza (coralroot), Cypripedium (ladies-slipper), Platanthera (rein-orchid), and Spiranthes (ladies-tresses). Identify the family by the irregular flower, inferior ovary, monocot leaves.
  10. Parsley Family (Apiaceae) - Biennial or perennial dicot herbs, mostly with white or yellow flowers borne in simple or compound umbels. Leaves alternate, usually compound or dissected, with sheathing leaf bases, often aromatic, sometimes toxic. Flowers regular, very small, with inferior ovary; with 5 sepals, 5 petals, 5 stamens, and one 2-parted pistil. Fruit a 2-parted capsule, separating into two sections at maturity. 53 species in New Jersey (30 of them native) in 34 genera, including Daucus (carrot), Zizia (alexanders), and Sanicula (snakeroot). Usually an easy family to recognize by the umbellate flowers, compound or dissected leaves, and 2-parted fruits.
  11. Carnation Family (Caryophyllaceae) - Herbaceous dicots with opposite or whorled, usually entire leaves, with swollen nodes on the stem at the leaf bases. Flowers solitary or in cymes; usually regular; mostly white or pink, often with petals notched; with 5 sepals (often united), 5 petals (rarely, none), 5 or 10 stamens; and one 2- to 5- parted pistil. Ovary superior, but the tube formed by the united sepals of some species may make it appear superior at first glance. 54 species in New Jersey (20 of them native), in 21 genera, including Cerastium and Stellaria (chickweeds), Dianthus (pink), Silene (campion and catchfly), and Spergula (sand spurrey). Identify the family by the opposite branching, regular 5-merous flowers, stem nodes.
  12. Buttercup Family (Ranunculaceae) - Dicot herbs or sometimes vines, mostly with variously divided alternate leaves. Flowers usually regular, solitary or in racemes or panicles, often showy, variously colored, though yellow and white are perhaps commonest; with 3 to many sepals (which are sometimes deciduous, dropping off when the flower opens), many stamens and many pistils. Easily mistaken for some flowers of the rose family, but the buttercups lack the receptacle fused to the ovary that is typical of roses. 48 New Jersey species (37 of them native) in 15 genera, including Ranunculus (buttercup), Anemone (wood anemone), Clematis (virgin's bower), and Aquilegia (columbine). This family can usually be identified by the flower structure, with a cluster of stamens and pistils at the flower center.
  13. Lily Family (Liliaceae) - Perennial monocot herbs. Flowers usually regular, often showy; more or less bell-shaped; growing singly or in spikes or racemes. In many genera the sepals and petals are similarly colored (and may then be called tepals); also, petals and sepals may be partly united to each other. Flowers have superior ovary, 3 sepals, 3 petals, 6 stamens, one 3 parted pistil. Fruit a capsule or berry. 51 New Jersey species (38 native) in 30 genera, including Lilium (lily), Hemerocallis (day-lily), Polygonatum (Solomon's seal), Alium (onion, leek), and Erythronium (trout lily). The 3-merous flowers with superior ovary make this an easy family to recognize, usually.
  14. Buckwheat Family (Polygonaceae) - Dicot plants, usually herbs but sometimes vines, with alternate, entire leaves and stipules which form a sheath (ochrea) around the stem at the leaf base. Flowers small; greenish, white or pink; usually in spikes; with 5 or 6 sepals (if 6, in two groups of 3 each); no petals, 3-9 stamens; and one 3-parted pistil. Fruit a lens shaped or triangular achene. 50 New Jersey species (30 native) in only 4 genera, including Polygonum (smartweed), Rumex (dock), Polygonella (jointweed), and Fagopyrum (buckwheat). Identify the family by the ochreae at the leaf bases and the flower structure; individual species by details of flower, seed, and ochreae.
  15. Heath Family (Ericaceae) - Dicots, mostly shrubs, with alternate, sometimes leathery and evergreen or sub-evergreen, leaves. Most abundant in acid soils, whether dry or wet. Flowers usually regular or nearly so, with 4 or 5 sepals that are often partly united, 4 or 5 petals, also often united, 8 or 10 stamens, and one 4- or 5- parted capsule. 31 species in New Jersey (29 of them native), in 15 genera, including Kalmia (mountain laurel), Vaccinium (blueberry and cranberry), Gaylussacia (huckleberry), Rhododendron (azalea), and Arctostaphylos (bearberry).