By Ranger Steve Mueller
The transition from spring wildflowers to summer wildflowers is nearly complete. The greatest difference is whether the plants flower under leafless trees or flower under expanded leaves.
It takes a lot of energy to produce flowers and seeds. It is best for plant sex to occur in full sunlight before trees cut off sun energy to the ground with leaves. I pay more attention to phenological summer beginning than to when the sun reaches its most northern zenith. Calendars mark the summer solstice when the sun no longer appears to move north and apears to start its southward movement.
Spring flowers end flowering when trees leaves expand and shade the forest floor. Plants wither or spend the summer without the flare of flowers while they store energy in roots, tubers, and rhizomes for next spring’s flowering. When sunlight penetrates through early spring branches of bare canopy, ground plants receive high-energy necessary flower sex.
Carpets of Narrow-leaved Spring Beauty flowers brighten the forest floor. The petals appear pink but they are not. Bend and look closely. You will notice white petals with pink lines. When we stand and look down, our eyes do not discern the detail. The pink lines on white petals act as nectar guides. Insects landing on the petals follow the lines like airport runways to nectar.
It is too late this year to take notice of these flowers but it will give you something to notice next year. The spring beauties complete their life cycle and disappear from view for ten months. Their nature niche activities occur between late April and early June. By late May fertilized flowers have formed seeds. Soon the entire plant above ground withers and is hidden below ground until next spring.
To ensure reproductive success this plant produces a series of short-lived flowers. A plant might remain in flower for several days but individual flowers come and go quickly. If poor weather prevents a flower from being fertilized, others blooming before and after will hopefully have had success on better days.
Other spring flowers racing to complete flowering before the forest canopy darkens the forest floor are Hepaticas, Trout Lilies, Bloodroot, Large-flowered Trillium, a variety of blue and yellow violets, with Mayapples squeezing in at the tail end before the canopy thickens. Each plant has it own unique adaptations and story with associated insects, birds, and small mammals. Stories abound.
An early summer plant that flowers in abundance as trees turn the landscape wonderful shades of green is Wild Geranium. It cheery pink blooms abound in forest and forest edges. For me it is a sign that summer has begun. It is still weeks before the summer solstice with the longest day of year and the official start of summer. The phenologies of plants have their own markers to indicate the end of spring and the beginning of summer. Oaks and mulberries are among the last trees to leaf out. Once they expanded their leaves, I consider spring to have ended and summer has begun.
Most trees flower before they have clothed themselves with new leaves. If they are wind pollinated, it best to flower when the wind can flow freely among the branches to spread pollen. Many are insect pollinated and it is easier for insects to travel from flower to flower without leaf obstacles. By the time maple leaves expand, the samaras helicopters are carrying seeds to the ground away from the parent. Non-descript oak flowers fall as withered tan strings but a portion will remain all summer to grow and loudly pound the roof, car, and ground as acorns in fall.
There is more occurring than one can notice but many notice summer blueberries come from spring bell-like flowers, pale current flowers usually do not attract our attention but we enjoy their summer fruits, and we notice of apples as they ripen. Take time to notice the beauty of life surrounding you.
Natural history questions or topic suggestions can be directed to Ranger Steve (Mueller) at firstname.lastname@example.org Ody Brook Nature Sanctuary, 13010 Northland Dr, Cedar Springs, MI 49319-8433. Phone: 616-696-1753.