The Valley is full of flowers in June. So many so that here we present them by type—here are the shrubs, which come into their own when in full flower. Separately, we will post Wildflowers in Sageflats and Hills/Sun and Wildflowers in Forests/shade.
Most shrubs are most appreciated in spring when they bloom, although some will have colorful foliage and fruits for a short time in fall. The rest of the year, shrubs are usually overlooked as just green bushes or just twigs. So now is the time to celebrate shrubs.
Note: Shrubs are woody plants usually between 6”-20’ tall with multiple stems vs. 1 or 2 trunks of a tree.
The following are more or less in flower sequence within their group.
First to Start:
Willows – Salix sp. – There are many, many types of willows of all sizes. They are very important for wildlife: pollinating bees, nesting birds, browsing moose, and dam-building beaver to name a few.
We usually welcome their early spring catkins—pussy willows. They come in male and female versions, are pollinated by insects (not by wind, as previously thought) starting in April. By late June the female capsules are bursting with thousands of seeds attached to a tufts of fluff being dispersed by wind. Along with their relatives the cottonwoods, they are creating blizzards.
The teensie seeds are viable for only a few days, and they must land on moist open ground to germinate. Only a couple of seeds out of a million will sprout and grow up at all. Plants, though, can propagate vegetatively from broken stems stuck in the mud, as along flooded rivers or around beaver ponds.
Utah Honeysuckle – Lonicera utahensis – has oval leaves that are arranged opposite each other on the stems. The trumpet-like, pale yellow flowers are found in pairs, their ovaries attached at the very base. Later twin red berries will loll upon the green of the leaves…but not until late July.
Oregon Grape – Mahonia repens – is one of our few evergreen shrubs and is particularly tough. It grows in sun or shade, often on very rocky soils. Several thick holly-like leaflets form along the central petiole to comprise a compound leaf. In spring the “evergreen” leaves remain, although a bit tattered, until the new leaves replace them. The flowers are remarkably fragrant and last a long time. The underlying bark is yellow with “berberine” which has medicinal properties.
Mountain Maple – Acer glabrum – has inconspicuous flowers that are pollinated by wind or perhaps some insects? Each flower is usually male or female to prevent self-pollination. By now in late June you can see the beginning of the fruits forming – the double winged samaras – that will twirl to new realms later in the fall.
The leaves are 3-5 lobed, with some saw-like teeth along the edges. Often I see the leaves mottled with a deep red “fungus”. The velvet red splotches are actually formed by tiny galls created by mites: https://www.canr.msu.edu/news/velvet_galls_caused_by_tiny_eriophyid_mites
A June Parade of White Blooms in the Rose Family:
These common shrubs grow from a few feet to up to almost 20’ tall. They all have five green sepals, five white petals, and anthers (the pollen bearing parts) in multiples of 5. These three whorls merge into a cup-like hypanthium that will later swell and protect the seeds. Hypanthium structures are common in the Rose Family. In the very center of this cup-like feature, sit the female ovaries and eggs that will form the seeds. The fruits will be a combination of swollen protective hypanthiums and the mature seeds in the center. (image wikipedia)
All these plants are related to cultivated fruits we eat: apples, plums, pears, peaches—also in the Rose Family. Our native roses blooms in July–very soon! and produce “hips” – the tough hypanthium with dry fruits/seeds inside.
More or less in order of bloom:
Serviceberry/Saskatoon – Amelanchier alnifolia – has oval 1-1.5” leaves with a few teeth arrayed around the upper ½. Flowers are arranged along a central stalk. Being one of the earliest to bloom, it will also be the earliest to fruit.
Chokecherry – Prunus virginiana – has 4-5” oblong, pointed leaves with fine teeth all along the edges. The dozens of flowers are stiffly arranged on the long central stalk. All the parts of the plant have a chemicals that can produce poisonous cyanide under certain conditions. For instance, if cattle eat too many of the spring leaves they can become very sick. Amateur entomologists have used the leaves and bark in jars to kill insect specimens. On the other hand, western tent caterpillars thrive in their branches, and birds and other mammals will eat the fruits come fall (the particularly toxic pits pass on through).
Black Hawthorn – Crataegus douglasii – are easy to ID with their ½-1” thorns. The broad oval leaves are coarsely toothed. The flowers are in branching bunches or cymes. In August, the Moose-Wilson Road is often closed due to bears feasting on the berries.
Mountain Ash/Greene’s Ash – Sorbus scoparia – begins to bloom in late June in slightly cooler locations. The leaves are “compound” with many leaflets coming off a central stalk. The stalk then attaches to the twig. The tiny flowers form a great puff of creamy white flowers at the end of the stems.
Ninebark – Physocarpus malvaceus – is found in the southern part of Jackson Hole flowering at the end of June. Unlike other white bloomers above, it will have dry fruits. Leaves are slightly lobed and toothed.
Yellow Members of the Rose Family Join In the Parade of Bloom:
Not all members of the very large Rose Family make luscious fruits. While also having hypanthiums, the cups remain thin and brown cradling dry seed-like fruits (achenes) inside. For now enjoy the flowers.
Antelopebrush/Bitterbrush – Purshia tridentata – is especially abundant this year. You can smell the sweet yellow flowers before you come over the rise of an open hillside. Plants are often intermixed with sagebrush, growing about the same size.
The nutritious plants are valued wildlife browse throughout the year, but particularly in late fall and winter by moose. Ants and mice relish the seeds. Also these plants can fix their own nitrogen with the help of bacteria growing in the roots. Therefore, these shrubs can grow in many tough conditions. Note their small leaves are three-tipped like those of sagebrush, but they are greener overall, and the edges curl under.
Shrubby Cinquefoil – Potentilla/Diasphora fucticosa/Pentaplylloides floribunda – is a favored landscape plant for its yellow flowers in early to mid-summer and its low maintenance. It can grow in a variety of soils from sun to shade – but prefers a bit of moisture, especially when in sun.
Nurseries sell a range “cultivars” with white to deep orange flowers. Our wild native is yellow.
More June Shrubs of Various Sorts –
These four shrubs prefer more or less moist and/or cool areas and grow into substantial plants.
Silverberry – Eleagnus commutata – has been flowering under the cottonwoods along the Snake and Gros Ventre Rivers from Wilson north. They are easily seen from the dikes and from Fall Creek Road.
The 2-3” silvery oblong leaves stand out in the shade on 6’-tall, erect colonial plants. Hidden in the foliage are yellowish, highly fragrant tubular flowers.
Red Elderberry – Sambucus racemosa – looks at first glance like Mountain Ash with its white bunches of small flowers and compound leaves. However, it is overall heftier with thicker stems and heavier leaves, and notably the compound leaves are opposite each other, not alternate up the stems. Also, plants have a foul odor if pinched or crushed. Its European relative – Sambucus nigra – is the source of sambucol, the anti-viral flu mediation.
Twinberry – Lonicera involucrata – is also a substantial shrub usually found near water. The 3-6” oval leaves are opposite on the stem, and the flowers are formed in pairs. (It is a relative of the early flowering relative Utah honeysuckle – see above.) Flowers are mostly yellowish and hairy with a “bract” at their base that can be greenish yellow but later turns deep maroon. Keep an eye out for caterpillars of Gillette’s Checkerspot butterfly (photo credit: Wikipedia) which require this species for their host.
Red-stemmed Dogwood – Cornus stolonifera – is loved by moose, other wildlife, and landscapers. In fact it is an appealing “ornamental” plant for its tidy oval leaves set opposite each other on the red stems, bunches of white flowers, and later white berries. Red winter twigs are a cheerful contrast against snow. “Cultivars” have been selected with brighter red stems, variegated leaves, bigger flowers and berries. The moose relish it as is, and the birds will carry off the fruits when ready. A great plant for a “wildlife friendly” garden.
Junipers are evergreen conifers. The tree-like Western Juniper – Juniperus scopulorum – grows in all shapes and sizes on our dry buttes.
This species has scale-like leaves.
The sprawling Common Juniper – J. communis – has sharp needles that are in whorls of 3 and grows here and there in sunny spots. Both produce “berries” which are technically fleshy cones that are relished by Townsend’s Solitaires and Cedar Waxwings. However, few realize that the cones take 18 months to form, starting in June, and only on “female” plants.
Not to get into the complications of “naked seed” plants and their evolution, suffice it to say that pollen is released from tiny structures,
and with luck land on females cones of a different plant. You need a microscope to really see what is going on, but with a handlens, you can observe the first bulge of reproduction.
Others shrubs not mentioned: The gooseberries/currants – Ribes sp., various huckleberry relatives – Vaccinium sp., and a few inconspicuous wind pollinated species. We save those for later.
Enjoy the shrubs of spring…more to come this summer!
Frances Clark, Program Coordinator
June 26, 2020