Botany Blog

Bladderworts are carnivorous plants that form tiny bladder-like traps capable of capturing small organisms. Most species in the Northeastern U.S. are aquatic but a few species are terrestrial. Purple Bladderwort (Utricularia purpurea) is an aquatic species that occurs in soft, quiet waters of the Atlantic coastal states and sporadically further inland. It flowers from July to September.

There are two main taxa of Highbush Cranberry found in the U.S., one native to Europe and the other to North America. The European Highbush Cranberry (Viburnum opulus) has naturalized throughout the northern half of the U.S. and is most easily identified by the presence of distally depressed (cup-shaped) petiole glands. The fruit of this species is unpalatable and mildly toxic.

The American Highbush Cranberry is sometimes treated as a variety of Viburnum opulus (V. opulus var. americanum) or as a distinct species (V. trilobum). Rather than being cup-shaped, the petiole glands of this shrub are club-shaped or columnar. In addition, the leaves often have short sparse hairs above and the lobes tend to be narrower. While the European Highbush Cranberry can be found in a variety of shaded habitats, its American counterpart is mostly restricted to rich woods or the edges of marshes or swamps. It has fruit that is sour but considerably more palatable than the European variety.

American Highbush Cranberry seems to be much less common in many parts of North America than the European. I have come across dozens of specimens in the wild in the last few years and none of them have been native. Then last week I found some native Highbush Cranberry on a research plot in the Tug Hill region of NY. The habitat was a reverting field at the edge of a marsh where the water table was very close to the surface. Here are some pictures.

Overall habit

Leaf shape

 Petiole glands

Hairy margin

This small plant is an annual hemi-parasite in the Snapdragon family (Scrophulariaceae) . It is associated with acidic, shady habitats on soils that can be peaty, sandy, or rocky. These plants were found along the edge of a pine forest (white pine/red spruce) on sandy soil. The genus name means “black wheat”; apparently when the seeds of this plant were added to other grains and ground into flour the bread made from this mixture turned out black (Borealforest.org, 2010).

The flowers are bilabiate and white with a yellow throat. Leaves tend to be lance-shaped or linear, with the upper often with a few long teeth near the base.

Bittersweet Nightshade (Solanum dulcamara) is an herbaceous vine in the potato family (Solanaceae). It is native to Eurasia but has naturalized widely in North America. It occurs in a variety of habitats provided sufficient light is available. Several features aid in identification. First are the purple flowers with five reflexed petals and bright yellow stamens

The fruit matures from green to yellow, orange, and finally bright red and resembles a small tomato (also in the potato family). The plant gets its name from the reputed taste of the fruit, which is said to be bitter at first but later sweet. While the fruits are said to be less poisonous than the rest of the plant, I have never dared to taste one as all parts of the plant contain solanine which is extremely toxic. While poisonings are rare, fatalities have been known to occur.

The leaves are somewhat arrow-shaped and often have two or more lobes at the base. The color is dark green and they seldom have evidence of herbivory. The smell of the leaves is perhaps this plant’s most distinguishing characteristic, similar to tomato but much more foul and disagreeable. This trait has come in handy when it has been necessary to identify seedlings in the field.

Study plants for any length of time and one will eventually hear the phrase “sedges have edges”. This is because the stems of sedges typically have three angles, distinguishing them from the terete (round in cross-section) stems of grasses. For quite some time that was about the extent of my knowledge of this group of plants. A few years ago I decided to get serious about learning sedges, particularly the species rich genus Carex. One characteristic of plants in this genus is that the achene (seed) is surrounded by a sac known as a perigynium (plural perigynia). Close examination of these structures and the scales subtending them is often key to proper identification of plants in this genus. The perigynia are relatively large and inflated in Shining Bur Sedge (Carex intumescens), shown below.

Recently I have been adding photographs and descriptions for Carex species to my Plants of the Northeastern U.S. website. One goal has been to document important details of the inflorescence using a dissecting scope including a ruler marked in millimeters. Recently added pages include those for Carex brunnescens, C. debilis, C. deweyana, C. disperma, C. hystericina, C. interior, and C. radiata.

Poison hemlock (Conium maculatum) is a biennial herb that can grow to 3 m tall. It has a smooth stem that is often purple-streaked or spotted. The leaves are broadly triangular and divided into 3-4 segments with finely divided leaflets.

The white flowers are produced in umbels up to 6 cm wide and rather resemble a large Wild Carrot (Daucus carota).

This species is native to Eurasia but has been introduced and has spread widely throughout North America. Most often found in partially shaded, disturbed areas on soil ranging from dry to wet, it is perhaps best known as the plant given to Socrates after he was sentenced to death. All parts are extremely poisonous but the parts of the plant that are most toxic are the seeds and root.

Squarrose Sedge (Carex squarrosa) is a sedge of swampy woods and thickets that can easily be identified in the field. A stout, tufted sedge that can grow to a height of nearly 1 m, it has inflated perigynia (sacs) with abruptly narrowed beaks that are tightly packed on 1-2 (sometimes 3) spherical to ovoid spikes. The term squarrose means spreading, referring to the arrangement of the perigynia on the spike. The persistent style of the achene has a distinct bend to it, distinguishing it from the straight or slightly curved style of Cattail Sedge (Carex typhina).

Below is a composite image of Common Mullein (Verbascum thapsus). This species has naturalized throughout most of temperate North America and typically occurs in disturbed areas. It is a biennial, most easily recognized by the low rosette of densely fuzzy leaves in the fall of the first year or spring of the second year. By summer of the second growing season it sends up a tall, dense spike of yellow flowers. Mature flowering stems can reach 2 meters in height.

Many years ago I developed a fascination with cold-hardy cacti. There are several Opuntia spp. (Prickly Pears) that naturally occur in the Midwest and one in the Northeastern U.S. (Opuntia humifusa).

Spinystar (Coryphantha vivipara) is quite different and only occurs as far east as Minnesota. It has bright magenta flowers and a single, cylindric stem. This species can be grown in the Northeast but may develop rot near the base if it is allowed to get too wet, particularly during cold weather. This is probably what naturally limits its range to the west.

The spring ephemerals are really brightening up the woods now. We are fortunate in central NY to have many calcareous woodlands boasting large populations of large white trillium (Trillium grandiflorum).

All trilliums are protected in New York State because they are considered exploitably vulnerable.  Plants are considered to be exploitably vulnerable when they are “likely to become threatened in the near future throughout all or a significant portion of their ranges within the state if causal factors continue unchecked” (NYCRR §193.3). While it may seem unnecessary to protect a plant that can be locally abundant, this and other trilliums are often lacking in forests with a history of disturbance, particularly forests that have established on formerly cultivated land.

References:

New York State Register and Official Compilation of Codes, Rules and Regulations of the State of New York (NYCRR) http://www.dec.ny.gov/regulations/regulations.html