Thursday, June 27, 2013

For SkyWatch Friday: How the Rain Ends

June 25, 4:17 PM, Temp 67.0° F, Dew Pt 57.3° F, Barometer 29.72 in, Wind 3 mph, Humidity 71%

Looking southeast, this is how the rain ends in the Pacific Northwest USA.  After two days of overcast and light drizzle, the skies cleared over Skagit Bay last Tuesday afternoon.  It was as pleasant to be out in the garden taking pictures as it looked.

Saturday, June 8, 2013

Cow Parsnip - Look But Don't Touch

The Cow Parsnip (Heracleum lanatum, H. maximum) in the Carrot family is a spectacular wildflower.  As its name implies, it accomplishes herculean proportions.  It can grow to 8 feet (>2 meters) in height and the flower heads can be a foot (30 cm) across.  The leaves are even larger.  They can be found growing from sea level to subalpine elevations throughout most of North America.

All of the plants pictured here are growing along the dike at Wiley Slough in the Skagit State Wildlife Recreation Area.  They also grow along the road where I live.  This year's display is especially impressive.  Greater than normal rainfall could be the explanation.  My weather station measured 2.64 inches (670 mm) of rain for April and 2.51 inches (640 mm) in May.  This is 1.66 inches (420 mm) above average for the two-month period.

I learned something important researching for this post.  As in the photo, the plants like to grow along trails and roadsides.  This provides opportunities for hikers and runners to brush up against them.  This should be avoided at all costs.  A group of chemicals called furanocoumarins are found in the sap and outer hairs.  On the skin, they can produce a rash after exposure to heat and/or sunlight in sensitive individuals.  The burning, itching and blistering can be intolerable and may recur over several months.  I have not experienced this personally, but now that I know about it, I will be more careful around the plants.

The giant compound flower is called an umbel because it is like an umbrella ("umbelliform") with spokes extending from a common point.  This perennial will die back every fall, but the giant seed heads will be held on the stems well into winter.

Close inspection of the flower heads revealed them to be alive with insects of all sorts.  Based on range, color pattern and elevation (here basically sea level), I have tentatively identified this bumble bee as Bombus mixtus, the Fuzzy-horned Bumble Bee.  See if you agree (.pdf).  Then look just below the center of the photo.  Can you spot the two tiny beetles also making a living on the flower?  Can anyone ID them?

Here's a nice video I found of B. mixtus in action.

This Tree Swallow occupying one of the many nest boxes along the Spur Dike Trail probably has some new mouths to feed.  Plants that are attractive to insects become elements in the food web.  The Cow Parsnip supports many species of insects which in turn become food for birds.  This illustrates one reason why the Cow Parsnip is more than just a pretty flower.  It is an important part of a balanced ecosystem.

Friday, June 7, 2013

Yellow Iris

Yellow Iris (Iris pseudacorus)

On Monday morning, I was hiking the Spur Dike at Wiley Slough in the Skagit River delta.  I came upon a vehicle and a group of people out on the dike, something quite unusual.  They were donning chest high waders and preparing spray cans.  I was curious about what they were doing.

Their mission was noxious weed control.  Recall that this part of the Skagit River delta is being restored to improve habitat for the endangered Skagit run of Chinook Salmon.  Their specific targets were Yellow Iris and Purple Loosestrife.

Yellow Iris (Iris pseudacorus) is a wildflower native to Europe including Britain, western Asia and north Africa.  It is a beautiful flower and revered by Europeans.  The famous Fleur-de-lis symbol of France is believed to represent the Yellow Iris.  In North America, it has escaped our gardens and become a threat to wetlands.  It can outgrow and displace native vegetation.  It will choke waterways and reduce the carrying capacity of wetlands for waterfowl.  For these reasons, it is included on the state noxious weed list.

Two years ago, I spotted one Yellow Iris plant out here.  At the time I thought it was a lucky find.  On this visit, there were several patches of it and some were quite large.  Obviously, it is beginning to spread and why it has become important to get it under control.

Purple Loosestrife (Lythrum salicaria) doesn't start blooming until late June, and I didn't spot any on this visit.  Its native habitat is roughly the same as Yellow Iris where it also likes to grow in fresh water and brackish wetlands.

As it happened, there was a second crew with vehicles out on the dike on this morning.  They had U.S. Government license plates on their trucks and they had a fish net in Wiley Slough.  They were doing a census of baby Chinook Salmon, measuring the fish and recording their findings.  It looks like the efforts to restore this habitat is showing success.

It turned out to be an interesting morning.  I got to observe two activities of habitat restoration going on at the same time.