Vitis aestivalis (Summer Grape)
|Also known as:||Silverleaf Grape|
|Life cycle:||perennial woody|
|Habitat:||part shade, sun; average to dry; deciduous woods, thickets, wooded bluffs|
|Plant height:||to 70 feet|
|Wetland Indicator Status:||GP: FAC MW: FACU NCNE: FACU|
|MN county distribution (click map to enlarge):|
|National distribution (click map to enlarge):|
Pick an image for a larger view. See the glossary for icon descriptions.
Cylindric clusters up to 6 inches long opposite the leaves of this year's new branches. Separate male and female flowers are typically on different plants, both 1/8 inch across or less with 5 green to yellowish petals that drop off early. Male flowers have 5 or 6 long, pale, erect to ascending stamens around a tiny button center. Female flowers have a bottle-shaped style and 5 short stamens that are usually sterile and somewhat contorted. The calyx cupping the flower is minute; flower stalks are minutely hairy and often red. Flowers are fragrant.
Leaves and stems:
Leaves are 4 to 8 inches long and about as wide, mostly broadly heart-shaped in outline, shallowly to deeply lobed with 3 or (usually) 5 major lobes and a broad gap between the 2 basal lobes. Deep sinuses between major lobes are often well-rounded. Edges are toothed, the teeth mostly rounded with a minute point at the tip.
The lower surface is covered in a whitish, waxy bloom, which is often obscured by reddish-brown, cobwebby hairs; major veins are also densely hairy. The upper surface is dark green and hairless or becoming so. Leaf stalks are 2 to 6 inches long, often reddish, hairy, more densely so near the leaf blade and more sparsely near the stem.
New branches are yellowish-green to reddish and hairy, the nodes covered in a waxy bloom. Forked tendrils develop opposite the leaves on first year branches, usually skipping every third leaf, and become woody with age. Older bark is brown to reddish-brown, hairless and shredding, peeling in long strips. A mature plant may have a trunk as much as 8 inches in diameter at breast height (dbh). Plants may climb high into trees or crawl over shrubs and lower vegetation.
The flower clusters become dangling as fruit develops. Fruit is a round berry ¼ to ½ inch in diameter, ripens from green to blue-black, and is covered in a white bloom. Inside a berry are 2 to 4 slightly flattened, egg-shaped seeds. Berries are often sour until after a frost, then turn more sweet-tart.
Summer Grape a rare species in Minnesota, limited to a few southeast counties along the Wisconsin border, where it reaches the extreme northwest edge of its range. Across its range, it's found in upland hardwood forest and forest edges, dunes, fencerows, and wooded bluffs, often in sandy soil and in areas of disturbance (natural or man-made). According to the DNR, biological surveys in the southeast over the last 20 years have only found 1 new location, bringing the total to 11 known populations, one of which was unintentionally destroyed in an effort to manage specific canopy trees. This illustrates the problem of managing an entire ecosystem as component parts rather than as a whole. Its habitat preferences in MN are not well understood and it was listed as a Special Concern species in 1996, elevated to Threatened in 2013.
It can resemble the related Riverbank Grape (Vitis riparia), which has leaves with sharply serrated edges, lacks the cobwebby hairs and waxy bloom on lower leaf surfaces, and is ubiquitous in floodplain forests and woodlands throughout the state, where Summer Grape prefers drier habitats. Summer Grape leaves may also resemble another vine, Common Hops (Humulus lupulus), which does not have woody stems or tendrils, has opposite leaves, and a cone-shaped fruit rather than berries. There are 3 recognized varieties of Vitis aestivalis, distinguished by fruit size, degree of hairiness, the amount of waxy bloom and other traits; var. bicolor, a.k.a. var. argentifolia, is present in Minnesota. Note that the population we encountered had sparse glands on at least some new stem growth, but there is no mention of glands or glandular hairs in any of the available references.
Please visit our sponsors
Native Plant Nurseries, Restoration and Landscaping Services ↓
- Summer Grape vine
- high-climbing vine
- vine climbing over shrubbery
- sparse glands on new stems
- sparse hairs on lower leaf stalks
- more leaves
- budding flower clusters
- new stem growth with red tendrils
- leaf shape can be quite variable
Photos courtesy Peter M. Dziuk taken in Houston County.
Have you seen this plant in Minnesota, or have any other comments about it?
on: 2017-08-15 20:26:43
Along the wood in my back yard I have watched the Riverbank grape (https://www.minnesotawildflowers.info/shrub/riverbank-grape) grow. It is over 20 feet high along the treeline, and follows about 100 feet along the forest. This year, I noticed a smaller grape plant along the same line, with clearly different leaves. Deeper lobes, and shaped differently. It is now about 3 feet high, with 3 vines. It is this summer grape, I am sure. Now, according to the map, this summer grape is only in s.e. Minnesota - but we are up here in St. Louis County, 2 hrs west of Duluth.
on: 2017-08-16 05:54:50
Annie, what you saw was most likely moonseed. The leaves are variably lobed and can resemble southern grape.
on: 2017-09-02 03:05:23
I posted that I saw this plant, however, I now believe it is the riverbank grape, with deeper lobes. I have NO idea why the same genus would have 2 very different leaves, but it looks just like this one, but with the riverbanks spiky edges. It looks just like the top pic in summer grape vine, but with the tiny spikes along the leaves, like riverbank. Sorry I can't take pics. If you can delete BOTH of my posts, so I don't throw people off, I would appreciate it. :/
on: 2017-09-02 06:21:27
Annie, it's really not so unusual for a species to have variably shaped leaves. And keeping your comments online may actually help others who might have a similar experience.
on: 2018-07-18 23:31:03
Annie, I have found what I believe are summer grapes near carver park myself. I've seen the USDA markers that they should only be found in the southern portion of MN. They appear green on the top, silvery white on the underside. There are 3 deep lobes with serrated edges. The vines have tendrils, unlike moonseed. I found them growing near river grapes.
on: 2020-08-16 12:24:31
This is definitely a rare species in Minnesota. The variety of Vitis aestivalis found here is called 'bicolor' for a good reason, the underside of the leaves is a distinctly different (bluish) color from the top of the leaves. So, by far the easiest way to distinguish it from the much more common V. riparia is to flip the leaf over and look for the contrasting coloration. By the way, this species is now being used by plant breeders to develop new types of cold hardy wine grapes, much the way V. riparia has been used to develop cultivars like 'Frontenac'.
on: 2022-07-09 19:36:12
I believe I have a plant growing along with river grape. We have a lot of river grape but this caught my eye and it is distinctly different and the characteristics match up with the description here. It doesn't have the hallmarks of moonseed.
on: 2022-07-10 04:55:48
I have to question reports of this species in the Twin Cities area. If they are correct, the DNR would want to know about them, but confirmation on the ID would be required first. Possible mis-IDs are the common riverbank grape, moonseed, or one of the hops species. The flowers are all different on these and can help with an ID. I suggest posting some images on the Minnesota Wildflowers Facebook page for additional assistance.
on: 2022-09-05 20:30:50
I will have to investigate this further, but I believe I spotted a vine on someone's fence inside Minneapolis. I pick Vitis riparia every year so I am very familiar with moonseed/hops/japanese ivy/creepers as lookalikes. I was examining the Vitis riparia on this fence and noticed the grapes on several in the middle were huge compared to any riverbank grapes I'd ever seen- at least 1/2th thick and a much different lighter color. The leaves were also a much lighter green. I came across this page while looking for other lookalike species, and will go back to the vine tomorrow to compare the characteristics.
on: 2022-09-06 07:07:38
Cole, if what you saw was in fact Vitis aestivalis (and it probably wasn't), it would not be a naturally occurring population in that location.
on: 2022-09-08 21:04:45
K Chayka, if the grapes I found were likely not Vitis aestivalis, is there another species I did not previously list that may be a lookalike? I've seen a lot of riverbank grape in my day. I am 99% sure it's not Vitis riparia.
on: 2022-09-09 06:24:06
Cole, have you considered cultivated grape? In any case, a vine on a fence in a residential area in Minneapolis is very unlikely to be naturally occurring population of this species.