Thursday, August 5, 2010

Blooming Shrubby St. Johnswort

The Shrubby St. Johnswort, Hypericum prolificum, at Blue Jay Barrens is in the middle of its blooming season and there are many flowers that are beginning to show their age. The older flowers darken in color and take on an orange tint before changing to brown.

Most of the St. Johnswort flowers area very similar in appearance. The tall, tapering pistil is surrounded by an explosion of stamens. The leaves of Shrubby St. Johnswort are thicker and stouter than those of other species.

Non-flowering specimens are hardly noticeable in the tall grass. Deer don’t find this to be a browsable shrub, so the shrub doesn’t suffer any damage from this big brown nibbler. Winter weather seems to play the biggest role in restricting the height of Shrubby St. Johnswort. Following a winter with below average temperatures, I see many of these shrubs regrowing from the plant base.

Older specimens develop a nice flaky bark on the stem. The base of the plant always has an abundance of active buds and is usually shooting up new stems. Snow protects the plant base from the super cold temperatures, so the plant is always ready to rebuild itself if necessary.

Shrubby St. Johnswort is not very common at Blue Jay Barrens. The largest concentration is the 20 or so plants that grow in this small opening. This is an area of subsoil left exposed by erosion years ago. The ground to the right falls rapidly down towards a drainage way and the area to the left heads gradually up hill to the ridge. The bare face of the advancing head cut that was working its way up the slope can be seen on the left. The erosion has stopped and the area has stabilized, but this area is virtually without topsoil. I think it’s odd that the Shrubby St. Johnswort isn’t growing in the deeper soil up the slope.

Some of the Mound Builder Ants are busy caring for a cluster of aphids on the St. Johnswort seed pods. The ants are quick to exploit any source of food within their territory, especially the sweet honeydew produced by aphids.

Honeydew is the sweet byproduct produced by sap drinking insects. Many species of insects produce honeydew, including several leaf hoppers. I’ve seen ants care for groups of leaf hopper larvae in order to gather the honeydew, but the adult leafhoppers don’t seem to be as willing to receive this ant attention. This leaf hopper is producing a droplet of what may be St. Johnswort based honeydew. I wonder if there would be a market for honeydew if it could be collected in sufficient quantities.


  1. If memory serves me, isn't this the 3rd species of St John's Wort that you've shared with us from Blue Jay Barrens? How incredible! They really are lovely plants.
    Steve, if you have a minute, could you stop by my blog to take a peek at a mystery insect that I've posted about? I mentioned it to you last year, but wasn't able to get any photos until this year. Thanks!

  2. Hi Steve...If you don't mind...may I ask how much land do you have !!
    This is a pretty flower and the leaves look health and shiny!! I would think they are happy !!
    Those seed pods are cute and seems the aphids like it there and the chain of nature and ants goes on!! ; }

  3. Heather - This is the 4th Hypericum I've talked about out of 7 species growing here.

    I was looking at your wasp post last night when storm clouds blocked my satellite. I'll make a comment there tonight.

    Hi grammie g. I've got about 107 acres. It's enough to let me wander a bit.