Common Water-primrose (Ludwigia grandiflora ssp. hexapetala) Engulfs Parts of Falls Lake, N.C.

Below is an inlet of Falls Lake located in Eastern Durham County.  Viewed from a car driving along a  quiet country road, the inlet looks like a lush pasture with a small pond at the end.  But the “crop” being grown here is a massive population of the invasive Common Water-primrose – Ludwigia grandiflora ssp. hexapetala, which has choked the entire inlet.  The “pond” at the end is one of only two spots of open water in the entire area.

Ludwigia grandiflora ssp. hexapetala Common Water-primrose Choking a Falls Lake Inlet

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose
Choking a Falls Lake Inlet

A closer look at the vegetative  mass, the beautiful individual flowers, and the deep green foliage.

Ludwigia grandiflora ssp. hexapetala Common Water-primrose

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose

 

Ludwigia grandiflora ssp. hexapetala Common Water-primrose

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose

Common Water-primrose spreads rapidly by sending out runners into any unoccupied spaces.  The growth and spreading process always starts with plants along the shore, but as the population grows farther out into the lake, runners can also be sent out from any part of the rooted or floating mass.

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose – Runners

Even peninsulas of land that extend into the open water become completely covered with the Water-primrose.  The plants root at the nodes so anywhere the runners contact soil, roots are established, and vegetative growth can continue at a rapid pace.      Within the area covered by the Water-primrose,  it is difficult to find any other plant life except for trees.

Ludwigia grandiflora ssp. hexapetala Common Water-primrose Peninsula

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose
Peninsula

Below is a photo of this inlet taken in October, 2012, after the blooming period is over.  The population then was not as extensive, allowing a view of the lake water.  This is followed by a photo of the same area as it is this July.  Note the large pole on the left in each picture.

Ludwigia grandiflora ssp. hexapetala Common Water-primrose October, 2012

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose
October, 2012

Ludwigia grandiflora ssp. hexapetala Common Water-primrose

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose

Another Falls Lake inlet, located in Northwestern Wake County, shows an earlier invasive stage, where the Water-primrose has not yet completely covered the water.  Note the large vegetative mounds along the shoreline.

Ludwigia grandiflora ssp. hexapetala Common Water-primrose

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose

In this area, runners have formed floating islands, and additional runners can be seen extending out from the these islands.

Ludwigia grandiflora ssp. hexapetala Common Water-primrose Floating Islands

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose
Floating Islands

The Water-primrose has colonized a large beaver lodge at the edge of the lake, shown in the two  photos below.  Beavers use mud to build the lodge and hold the structural poles and sticks together.  The Water-primrose’s runners take advantage of the mud, rooting as they go, climbing all the way to the top of the lodge.

Ludwigia grandiflora ssp. hexapetala Common Water-primrose Beaver Lodge

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose
Beaver Lodge

Ludwigia grandiflora ssp. hexapetala Common Water-primrose beaver lodge

Ludwigia grandiflora ssp. hexapetala
Common Water-primrose
beaver lodge

Common Water-primrose has been a problem plant for years at Falls Lake, and has a huge impact on vegetative diversity.  In addition to physically clogging waterways and lowering oxygen content, Water-primroses are also allelopathic plants, in this case secreting substances that inhibit or harm other plants nearby.  The shallow inlets of Falls Lake appear to be a nearly perfect environment for the spread of this invasive plant.

Herb Amyx

Invasive Common Water-primrose was mentioned in a previous article on the Mitchell Mill State Natural Area.    https://bwwellsassociation.wordpress.com/2015/07/10/an-early-july-glimpse-of-the-mitchell-mill-state-natural-area/

 

 

 

 

 

 

 

 

 

Advertisements
This entry was posted in Uncategorized and tagged , , , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s