Wednesday, March 16, 2011

Hardship on a Bare Slope

My first impression upon seeing these pink strands arching from the ground was one of electric wires. Oh no! Blue Jay Barrens is a robot. That would explain why things here are just a little bit odd. Of course, these are not wires at all. They are a natural part of Blue Jay Barrens’ organic component.

The pink strands are exposed roots of a Gray Goldenrod. The basal rosette of healthy green leaves can be seen clustered in the center the dead leaves from last season. This plant succumbed to a condition known as frost heave, the action of alternating freezing and thawing of the soil. Frost heave is most common when the soil is saturated. The water between soil particles freezes and expands, causing the soil particles to move apart and push upward. The ice locks around the roots and crowns of plants and if the roots are not strongly anchored, the plant is forced upward. When the ground thaws, the soil particles fall back and the plant roots are left exposed. Each successive freeze and thaw cycle pulls the roots a little bit further out of the ground.

This type of frost heave is not normally a problem on steep slopes where the water can quickly drain away and allow the soil to dry. This year was an exception because the weather patterns didn’t allow time for the ground to dry before freezing. A common occurrence this winter was a rainfall ahead of an approaching cold front, followed by strong winds and a plunge into sub-freezing temperatures. The cold wind hitting the slopes began the freezing process almost immediately.

Areas of bare ground are most susceptible to frost heave. Vegetative cover protects the soil by slowing the process of freezing and thawing. Growing among other plants also lends support and helps to anchor the root system more securely in the ground. Frost heave often results in the death of the plant, but in some cases the plant seems unfazed by its new situation. Gray Goldenrods will often develop new roots below the rosette of leaves and establish itself in its new location.

There are many variables that come into play to cause a plant to lift out of the ground. The presence of a little extra mulch or a more secure anchor for the root system could protect the plant from movement. Most of the Gray Goldenrods growing on this slope managed to stay in place during the changes in weather conditions.


  1. Fascinating information once again.

  2. Hi Steve...I have actually seen what you have described happen...instinct of survival !!
    Sounds something like my life story. lol

  3. Hi, Mike. Watch for this to happen in places where there are lone plants surrounded by bare soil.

    Thanks, Lois.

    Hi, grammie g. A good snow cover helps keep this from happening, so your plants should have been pretty safe this winter.