Weather

By Kristen Travers

April and May showers may bring flowers but for our streams rain can also bring problems. Recent rains have resulted in our streams resembling unappetizing chocolate milk more than the clear clean water that we want to see.

Before many people lived in the Delaware region, most of our area was covered in forests, wetlands and marshes. When it rained most of the rain water would slowly infiltrate (soak) into the ground and into the groundwater. Today our landscape also includes homes, businesses, and shopping centers. Rain water can’t soak through impervious surfaces such as roads, building and parking lots but instead runs over these surfaces picking up contaminants and sediment and quickly flowing into our waterways.

Data on our local streams clearly shows how as stream flow increases during storm events, so does the cloudiness of the water as measured by turbidity – a measure of the relative amount of suspended particles such as sediment.

Bare soil, dirt exposed from poor construction and farming practices, and stream bank erosion caused by excessive flows cause increased turbidity. Muddy water harms aquatic life, smothers habitat, and increases water temperatures. It can also be a health concern to drinking water sources and recreational uses since harmful microbes found in animal and human waste bind to soil particles.

Providing opportunities for rain water to slowly infiltrate into the ground can keep pollutants and sediment out of our waters while reducing flooding

Rainwater and soil are assets that should be kept in place:

  • Soak it Up: Add native shrubs, trees or perennial plants who’s deep root systems help to break-up soil and promote infiltration, while also holding the soil in place.
  • Cover it Up: Cover bare soil with mulch and more importantly plants!
  • Prevent It: Minimize chemical use on lawns and in our houses, don’t mow right up to the creek, and pick up after your pets.

Thank you to the volunteers involved with the Delaware Nature Society Stream Watch, White Clay Wild & Scenic program, and Nature Conservancy Stream Stewards for their dedication to monitoring and improving the health of our waters.

By Robert Fisher, Abbott’s Mill Nature Center Intern

Southern Delaware’s lingering drought received a brief respite on July 19th.  At 2pm severe thunderstorms rolled into the Milford area, bringing heavy rainfall. This steady inundation brought much needed moisture to stressed plants. While the rain was a blessing for most plants, the storm’s associated lightning and wind had a dramatic effect on some of the Milford Millpond Nature Preserve’s  trees.

This Tulip Tree was struck by lightning during the July 19th storm.

Abbott’s Mill naturalists prepping for a Native American program in the Lindale Tract encountered an abundance of tree debris and also discovered an impressive lightning strike on a large tulip tree (Liriodendron tulipfera), also known as yellow poplar.  The trees appears to have survived, but it will bear the marks of the strike for the rest of its days.

 

Path of the lightning through the tree.

The long scar, which runs the length of this impressive tree, tells us about lightning attraction and how trees handle it.  Tulip trees, being one of the tallest and fastest growing hardwood species in the eastern United States, have a  high biomass.  The combination of height and girth make these trees excellent conductors of lightning in the forest.  However, sap is a poor conductor and in a lightning strike, is superheated, becoming steam.  From this rapid expansion of liquid to a gas, an explosion occurs. The photo below shows fragments of bark and sapwood blown off of the tree, accounting for the exposed wood.  Shards of wood were found over 50′ from the tree and throughout the sub-canopy forest layer.

Debris from the strike covers the surrounding area.

The high visibility location of this tulip tree on the Lindale Loop Trail will serve as a teaching point for years to come.  If you are interested in seeing the tree for yourself, stop by Abbott’s Mill Nature Center and pick up a trail map highlighting our miles of hiking trails.  However, you might want to check out the chance of thunderstorms in the area before you venture afield!

 

Shard of the tree spiked in the ground.

By Joe Sebastiani, Seasonal Program Team Leader

If we could send a cool breeze through your computer screen this week, we would.  Nature is adapting to the hot conditions outdoors at Ashland these days through a number of means.  For instance, I took a quick walk by a small creek yesterday and spooked up a huge number of Gray Catbirds and American Robins that were bathing and taking advantage of the cooler micro-climate.  If you see a bird in your yard on a hot day, take a look…it might be panting like a dog.  Other animals like White-tailed Deer and Red Fox become very nocturnal.  Birds like a Red-tailed Hawk might take a flight into high altitudes to cool off. 

Here are a few photos from a colder season to help you deal with the heat this week.  I will still take summertime!

Delaware Nature Society Teen Naturalists after a hike to The Pinnacle in the Pennsylvania Appalachian Mountains a few years back.

 

Remember the days when we had to snowshoe in order to take a hike at Ashland?

 

Maybe you are wishing you were freezing in Nebraska...like we did on our trip there in March, 2009.

 

How about a December birding trip to the Delaware City Waterfront, complete with sideways icicles?

By Derek Stoner, Conservation Program Coordinator

A handful of hail stones, some as large as grapes. Held by Shannon, one of the DNS summer camp interns. Image by Derek Stoner, June 9, 2011.

Tonight at about 7:47pm, a fast-moving storm front passed over Ashland Nature Center, unleashing a fury of hail stones in a five-minute span.   In the midst of a training session for summer camp, our group dashed back inside and listened to the loud thwacks of hail striking the roof and windows. 

I ran outside to gather the larger hail stones, some of which were the size of grapes!  The icy cold hail provided a stark contrast to the 100-degree temperature earlier in the day.

Today’s heat wave set the stage for classic late day thunderstorm, and we certainly got a storm, albeit a very brief one.  Hail is one of nature’s most fascinating phenomena and one that certainly leaves an impression– sometimes literally!  The welt on my head is a testament to one hail stone that did not miss me.   We can only hope that the nesting birds and all the other animals did not get injured by the frozen projecticles hurtling from the sky!