July 10, 2018

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Dear Skyliners,

We're still hitting the Scattergrass (Ehrharta) hard.  Both outings last week were in the Bay Grove, where we weeded out one-year seedlings that are coming to flower.  Overall in the area, we're about 95% of the way there in Scattergrass containment, so steady as she goes.  Native bunch grasses (Melica torreyana) that we planted there last January are doing really well and now making their own seeds.  The long term outlook there is great!

 

We're going to try shifting our mid-week outing to Thursday afternoons at 4 pm for the summer.  Hopefully the date change will work with most of us.  Please note that we're also shifting the time to 4pm.  This will mean we can enjoy sunsets and the first stars.  Sunday will still be from 9:30 am to 1pm.

 

Please let me know if you can make it.

 

Ruderals - that's a new word to many of us.  In Botany, ruderal means a plant who grows in disturbed or waste areas.  In terms of plant succession, ruderals are the colonizers that first grow in open ground.  In lowland California, many common invasives are also ruderals, such as, thistles, Hemlock, Wild Oats (Avena), Bromes, Burr Chervil, and French Broom.  We have learned these all too well at Skyline.

We have nearly eliminated these invasive ruderals in many places, and so we're beginning to meet the native ruderals and learn how they behave in colonizing open or rough ground.  The most common native ruderals at Skyline are Tarweeds (Madia sp.), Wild Rye (Elymus glaucus), California Brome (Bromus carinatus) and Coyote Bush (Baccharis).  And, some of our wildflowers also behave like ruderals and those include Clarkia, Everlasting (Pseudognaphalilum calif.), and the Lupines.

 

We have especially noticed how quickly the Tarweeds move in.  The first year there may be just a few, but they are vigorous seeders and by the second year, they can nearly dominate in spots.  This then sets up the conditions for the colonizing shrubs, such as Coyote Bush, but also Gooseberry, Coffeeberry, Elderberry and Sticky Monkey.  It is so interesting to watch this succession drama with all of them being native plants.  This is a rare treat in lowland Calfornia, as the invasives are almost always present.

 

So, let's take a closer look at these Tarweeds and their ecology.  They are members of the Aster (Sunflower) family that are known for the sticky drops of aromatic oil on their leaves and flower buds.  The Tarweed who is blooming right now along the Skyline Trail is the Coast Tarweed, or Madia sativa.  These are tall, rank growers.  They often bloom in the evening.  Since Tarweeds usually bloom in the warmer months, this seems to be a successful strategy to protect their flowers from being burned by the hot sun.

 

Here is Coast Tarweed in full bloom: