National Wildflower Week 2024 – Day 2

Lady Bird Johnson said wildflowers “give us a sense of where we are in this great land of ours.”

Always the first full week of May, National Wildflower Week commemorates the colorful blossoms that bring our landscapes to life.

To celebrate this week, I encourage you to visit one of our area nature preserves, parks or trails to view the wildflowers now in bloom locally. Each day of this week-long celebration, I’ll feature a local native wildflower that you may find in bloom at this time.

To continue this week’s focus on wildflowers and for your self-guided search today, I suggest that you go looking for Early Meadow Rue (Thalictrum dioicum). See below for my suggestions as to where locally you can find this native forb.

Distinguishing Characteristics:

This perennial wildflower is up to 2½’ tall and across.  Stems are erect, hairless, pale green to purplish green, and often branched in the upper half.  Each branch has alternate compound leaves each comprised of 3 or 5 leaflets.  Individual leaflets are up to 1¾” long and across; they are orbicular to oval-orbicular in shape with 3-9 terminal lobes (usually 5 or more).  These short lobes are well-rounded or bluntly pointed.  The upper surface of each leaf is medium green and smooth, while the lower surface is pale green with a conspicuous network of raised veins; both sides are hairless.  All of the leaflets have slender stems (petioles).

The central stem terminates in a large floral panicle up to 1′ tall and across; each branch of the panicle terminates in a corymb of about 5 flowers.  Early Meadow Rue is dioecious, which means that some plants produce all male (staminate) flowers, while other plants produce all female (pistillate) flowers.  The male flowers droop downward from their branches to a greater extent than the female flowers.  Each male flower is about ¼” across and ½” long; it consists of 4-5 sepals and 10 or more stamens.  The sepals are broadly oblong, pale green, light-veined, and white-margined; the stamens have long yellow anthers and slender filaments.  Each female flower is about the same size as the male flower; it consists of 4-5 sepals and up to 15 pistils.  Neither male nor female flowers have petals. There is no floral fragrance.  The male flowers of Early Meadow Rue are more showy than the female flowers; this is primarily because the anthers of the male flowers are yellow, while the styles of the female flowers are dull-colored.

After flowering plants die down during the summer, low basal leaves develop during the fall. Their appearance is similar to the alternate compound leaves described above.

Where Found:

Early Meadow Rue prefers partially shaded woods and thickets. Habitats in which you may find it include rich mesic woodlands, wooded clay slopes, shaded areas near cliffs, and rocky ravines. It is common in forests with a lot of Sugar Maple (Acer saccharum) and American Basswood (Tilia americana).

• Ashford Glen Preserve
• Community Connector Trail
• Fox Preserve
• Garnsey Park
• Historic Champlain Canalway Trail
• Shenantaha Creek Park
• Vischer Ferry Nature and Historic Preserve
• Zim Smith Trail

Ecological Significance:

In botany, there is a scale called the “Coefficient of Conservatism.”  The scale represents how tolerant a plant is to human disturbances and how representative it is to a pre-settlement natural community of plants.  Coefficients of conservatism (“C” or CoC values) are increasingly being used to prioritize natural areas for conservation as well as for the monitoring of outcomes of habitat restoration projects. Species least tolerant of human disturbance and with an affinity for high-quality native habitats are placed in category “10.”  Early Meadow Rue is placed in category “7.”

SOURCE: Bried, Jason & Strout, Kerry & Portante, Theresa. (2012). Coefficients of conservatism for the vascular flora of New York and New England: inter-state comparisons and expert opinion bias. Northeastern Naturalist. 19. 101-114. 10.2307/41495840.

Because they are pollinated by the wind, the flowers of Early Meadow Rue are not showy and they do not produce nectar, thus not attracting pollinators.

The caterpillars of the Canadian Owlet (Calyptra canadensis), Meadow-Rue Borer (Papaipema unimoda), Straight-Lined Looper (Pseudeva purpurigera) and White Striped Black (Trichodezia albovitatta) rely upon Meadow Rue species as a host plant.

White-Tailed Deer (Odocoileus virginianus) browse on the foliage of Early Meadow Rue sparingly.  Nongame birds and small mammals may consume the seeds.

How to Grow Your Own:

Early Meadow Rue grows well in moist garden soil in a shaded spot that gets plenty of sunshine in the spring before the trees leaf out.

These plants are easy to grow from seed, though they will take some time to germinate and produce mature plants. It’s actually best to plant seeds collected from flower heads, as commercially sold seeds often have a lower germination rate. Patience is key. When direct-sown in the garden, seeds can take a full year to germinate, and two to three years until they reach flowering maturity. Seeds can simply be broadcast over an area where you want them to become established.

Because the plants often go dormant by mid-summer, the thoughtful gardener will want to keep track of where the dormant roots are located so that they are not accidently dug up or damaged.

To learn more about this native wildflower, please view my prior post What Wildflower Begins Blooming This Week? (May week 1), published on 5/7/2022.