The Green and White Season

Mock Orange, Philadelphus spp. has fragrant white blooms. There are several native species, but a non-native one is commonly found in gardens and landscapes.

Late spring and early summer in the forest is a little less colorful than early and mid spring. The canopy has closed, preventing as much sunlight from reaching the forest floor and the spring ephemerals are fading away. A lot of the plants in bloom during this time have white flowers. Many are shrubs as well which is interesting. A former supervisor of mine called this time in the forest, the green and white period. 

Oxeye Daisy, Chrysanthemum leucanthemum, is a widespread non-native summer wildflower.

White blooms during this time are not limited to the forest interior. Roadsides and forest edges commonly sport our first flower in the line-up. While not native, Oxeye Daisy, Chrysanthemum leucanthemum, is extremely common and can make its home just about anywhere there is enough sun. Like other non-natives, it does especially well in disturbed areas. This might just be the one wildflower that anyone can name. 

There are several different species of beard-tongues, Penstemon spp. There are three on the preserve that are separated out by small details such as glabrous anthers.

One of my favorite early summer wildflowers happens to be the white colored beard-tongues. Beard-tongues belong to the genus Penstemon and show up fairly often as cultivars in the horticultural trade. These flowers are really great for many different kinds of bees. According to Heather Holm in her book, Pollinators of Native Plants, small carpenter bees, European wool carder bees, digger bees, sweat bees, mason bees, leafcutter bees and bumblebees all regularly visit these flowers. Wow!

Penstemon flowers are protandrous, which means on each flower the anthers release their pollen before the stigma becomes receptive. It is in this way that the plant can help ensure cross pollination.

Wild white indigo, Baptisia lactea, is primarily a tall grass prairie plant, but there are a few populations found in Ohio. It is listed as potentially threatened on Ohio's Rare Plant List. On the preserve, it is only found in a few of the prairie openings. Regardless, it is one cool plant! Queen and worker bumble bees,  Bombus, are the main insects who can effectively pollinate this plant. 

This queen bumblebee, Bombus spp., comes in for a landing on wild white indigo, Baptisia lactea.

When flying to the tall flower stalks, the bees typically land on the lower flowers and work their way up to the top most flowers. The flowers open and start to mature from the bottom up as well. This causes the bottom flowers to enter the female phase before the top most flowers. As the bees visit from bottom to top, the pollen from the top flowers is transferred to the bee who then flies to a different flower stalk landing at the bottom where the flowers are ready to accept the pollen. What a wonderful and elegant relationship between the plant and the bee!

The pollen baskets seem heavily laden with bright orange pollen on the legs of this queen Bombus.

Next up is a very common and somewhat "weedy" plant but nonetheless a native one. Fleabanes, Erigeron spp., are lovely tall plants with aster or daisy-like flowers. Sometimes tinged with pink, they are typically white and sport bright yellow central discs. There are several species and the preserve boasts four in total.

Common fleabane, Erigeron philadelphicus, is the first of the four fleabanes to flower on the preserve in the spring. 

Next up is a diminutive yet cheery group of wildflowers in the genus Hustonia. There are four different species found on the preserve and can be found in a variety of habitats. These flowers are often white but can range from a pale lavender to pink as well. Aside from being pleasing to the human eye, they are a good source of pollen and nectar to the smaller native bees such as sweat bees.

Collectively known as bluets, the genus Houstonia has many different species. There are four on the  preserve.

This lovely houstonia is a pure white making it stand out well against its narrow green leaves.

Moving on to a couple of outstanding native shrubs, first up is one of my absolute favorites. Ninebark, Physocarpus opulifolius, is a fantastic shrub that I wish was used more in landscapes. It has a lovely shape, beautiful flowers and interesting bark. The flowers attract bees and other pollinators then later the seeds will attract birds.

Ninebark, Physocarpus opulifolius, is a wonderful native shrub that is beneficial to wildlife and a pleasing addition to the home landscape.

The second native shrub I'd like to highlight is one that is only found on acidic soils. Mountain laurel, Kalmia latifolia, is an evergreen shrub with a gnarled and twisty appearance. It is a sure sign that you are in a forest with dry acidic soils. I just love this one. It is so distinctive in the way it looks and has so much character.

Bright white flowers against the dark, waxy, evergreen leaves makes for a beautiful contrast in the early summer forest.

Mountain Laurel can form pretty dense thickets and in some areas are a prime nesting spot for warblers such as the black-throated blue. Deer will browse the leaves and tender twigs and the fruits are eaten by songbirds. There are also many kinds of insects that feed upon the shrub, including a long-horned beetle that will bore into the twigs.

The flowers are in clusters and are often more towards the top of the plant.

Pollinated best by bumblebees, mountain laurel employs an aggressive strategy to deploy its pollen. Each stamen is firmly held against the flower petal until triggered by the touch of an insect (or anything else for that matter). Then the stamen is propelled forward launching a sticky glob of pollen at the insect! Talk about taking initiative! 

Mountain Laurel, Kalmia latifolia, only occurs in a couple of places on the preserve. It prefers dry acidic soils.

For our last white flower, here is one that was new for me this year. This is low false bindweed (a terrible common name for such a pretty flower), Calystegia spithamea. This beauty belongs to the morning glory family as you may have guessed, but it is not a vine like the other morning glories. It is an upright plant with a fabulous, single large white flower. A real showstopper and wonderful plant for the last one our tour of the green and white season!

A very fresh flower of low false bindweed, Calystegia spithamea.

Posted by: Robyn Wright-Strauss