OUR THIRD JULY IN GARBER--OLD THINGS AND NEW THINGS

Our July 21st workday in Garber Park brought old friends to challenges, old and new.  As in past Julys, we noticed the approach of Fall in the Big Leaf Maple leaves, this time still lingering on their branches, but browning nevertheless.
On the way to our work site on the lower loop trail, we noticed the pervasive invasion of Erhardta grass on the cool slopes below the switchbacks.  Besides serving as a basic element of a fuel ladder, this exotic  grass proliferates easily and chokes out other plants, including seedling trees.  We decided to clear it from the lower loop trail in the delicious shade of the thimbleberry bushes.  As we worked on the trail we noticed several other early aspects of Fall, including the bright red

Thimbleberries , and the overarching Vicia gigantia, Giant Vetch, which

 had already set seed.  We made a mental note to return and harvest some of the Giant Vetch seed for later scattering in the Measure DD area by the creek.  The Horsetails from the upper meadow are moving into that area and Giant Vetch would thrive there also.

Towering over all of this, we also noticed a blossom that seemed unusual here, though it is not uncommon in East Bay woodlands--Holodiscus discolor known as Creambush or Oceanspray.  Apparently this lovely native is suitable for native gardens and highly regarded as decorative, but we had not noticed it previously among the Snowberries, ferns, Thimbleberries, Gooseberries, and other plants near the creek. 

All this time our special visitor, Janet Gawthrop of CNPS, had been laboring under the low  branches of the Garber Oak to remove outlier Cape Ivy from the high banks of the creek where newly opened spots of sun would invite its spread.  The removal of Cape Ivy remains one of the largest challenges for the Park, especially the wetland areas where it quickly becomes embedded, and has to be removed to the root and carried off site in bags.

 From Janet's vantage, we glanced down into the lower Coast Live Oak forest, so far, we believe, free of Sudden Oak Death infection, but harboring a number of juvenile Bay Laurels, primary vectors for the disease.  In the past Fall has meant a double load of clearing chores, seed collection, and preparation for restoration planting.   This Fall however, facing and searching for a remedial strategy with respect to Sudden Oak Death will take place as a high priority.   Can we keep the lower oak forest in tact?  Can we understand the natural future of each of our distinctive Garber forests? 

Summer Weeding

Janet removed Cape Ivy revealing a beautiful
stand of snowberry.

The good news for our first restoration workday of the Summer is that Garber is looking good - all of our plantings over the past two years are thriving, including the Measure DD Project on Harwood Creek.  The bad news - the weeds are also thriving, especially the cape ivy, poison hemlock and Himalayan blackberry.  More good news - we made good progress on the weed eradication front.  Janet attacked the cape ivy near Harwood Creek, uncovering a beautiful stand of native snowberry.  This is definitely an area to continue removing the cape ivy.  John and Clyde made great headway at removing the blackberries that are once again threatening to take over at Harwood Creek.  Sally and Shelagh cleaned up the Evergreen Entrance, Sally raking the steps and cleaning up Fireplace Plaza and Shelagh began weeding the planting beds.  I'll let the pictures tell the story.

Clyde, who usually attacks our biggest broom
in the most difficult spots, went after
Himalayan blackberry today
NEXT RESTORATION WORKDAY:  TUESDAY, JULY 3 @ 10AM.  We will continue weed abatement of the fire prone weeds.  The ground is drying up and fire season is right around the corner.  We hope you can join us.

John attacked the blackberries
at Harwood Creek.

Sally cleared the walkway and
steps at the Evergreen Lane
entrance

And Shelagh spent her time weeding the
restoration beds.

EARLY, EAGER BANANA SLUG/////// JUNE 5, 2012 GARBER WORKDAY

Early, Eager Banana Slug

The morning of June 5, 2012 was cool and brisk.  I had high hopes for our mid-week workday and as I was waiting for the arrival of our group of Japanese students (honing their English language skills in the English Language Program at UC), an early, eager banana slug tried to sign in.  We never know where our volunteers might come from.  I talked him out of it on the grounds that the meadow was too far for him to travel.  And by then, a van full of our volunteers had arrived.

"BEFORE"

The goal for the session was to begin, modestly but strategically, a long planned attempt to control the very invasive Cape Ivy infestation in our central meadow.  To do this, the tried and true method of starting with the outliers seemed appropriate, especially because the dense stands of Cape Ivy in the inner meadow were moving west and had surrounded a youthful Box Elder tree.  Liberating this lovely little tree so that it could reach the magnitude of its probable parent across the way looked do-able in one session.  We went for it.  

Our Volunteers, Clyde in Tree

Our volunteers split into two groups, one working on the west and one on the east of the Box Elder.  In about an hour, we had filled four large bags with pulled Cape Ivy, invasive Blackberry, some Algerian Ivy, and miscellaneous smaller invaders.  It is always surprising how much can be accomplished by a good group of dedicated workers.  In almost no time, it seemed, we had cleaned up the invasives from the neighborhood of the Box Elder. 

 In fact, we had enough time to pack up our gloves and tools and return to the Evergreen entrance for a little English language practice.  By noon, the Box Elder had been liberated, the Banana slug had found something else to do, and Clyde and myself were thinking about the next work day, June 17!!

"AFTER"

Thanks and Good Luck to our volunteer Japanese students!!

MAY 19, 2012-MEASURE DD MONITORING-UPPER MEADOW TO MIDDLE CONCOURSE

May 19, 2012--The Garber Park Stewards saved this mid-year workday for a task slightly different than the usual invasive removal chores.  We wanted to take a good look--at the beginning of summer--at the Measure DD plantings along the banks of the middle portion of the creek, mostly for recordation and monitoring purposes.  We were happy to have a couple of seasoned volunteers to help with this sometimes wet job and we were pleased to see our best broom remover, Clyde and his eponymous weed wrench.  This allowed us to do two really necessary things at once.

     Working our way up the creek from the bridge on the lower branch of the loop trail, we were happy to find almost all the red and blue flags that we thought would be there.  The blue flags marked Oregon Ash plantings and the red flags marked willow plantings taken from the stalks of nearby willows.  Altogether we found five Oregon Ash plantings, the tallest of which was a little over four feet; and 15 willow plantings, everyone in good condition, the more shaded ones with a few more leaves.  We were able to measure and photograph each of these.
     While Jon and myself were measuring willows, Clyde went north into the deeper canyon of the creek and came out with a pile of big stemmed French broom which had passed the blooming stage and had set seed.  We will get that pile out on June 5 when the Weed Warriors return to the area to clean up some of the inevitable regrowth in the Measure DD area.

     So we got a lot done, but we owe it to Jon, who turned his car around and came back and reminded us to use the new SOD brush to get the organic matter off our shoes at the end.  IS THERE SOD ON YOUR CLOD?--We are probably the first people to use the brush.  I certainly hope we are not the last.

Mary Millman for
Shelagh and Bob Brodersen--On Vacation!!

CLEAN IT, GREEN IT, MEAN IT: Earth Day 2012 Garber Park

The City of Oakland's Earth Day activities advertised more than 90 sites for folks who wanted to get outside and do some eco-friendly cleaning.  Being a secluded wildland Park, Garber has few mass attractions to offer--mostly at this time of year, a whole bunch of weeds to pull.  So the Garber Park Stewards were delighted to see a motivated turnout from the immediate neighborhood who came for the express purpose of pulling weeds.  By the end of the session, approximately noon, we could say that we cleaned it, we greened it, and from the beginning, we meant it.

In the upper portion of the restoration site at the Evergreen Entrance, we had left one bed unscraped and unplanted with natives.  We called this our control bed and having had 14 months of undisturbed growing time, this area was a complete wall of weeds.   Since the ground was still wet we decided to tackle it, not totally easy in view of the steep grade of the hill.  When we got into it we saw that Erhardta grass was the main offender, but looking deeper we found thistles, broom, forget me nots, poison hemlock, Himalayan blackberry, a few prunus sprouts and NOTHING native--which pretty much proves the point: invasive weeds prevent the establishment of native flora. 

Of course there were some weeds in our native beds as well, but the story there is very good.  Almost everything that we planted over the past year and a half is thriving and reproducing.  The native grasses are notable and will, with very little maintenance, come to dominate the hillside over the next year or two and hold it in place against inevitable erosion.  Even the native strawberries are fruiting.  We were happy to see a large volunteer population of Miner's lettuce in the lower beds, and to our surprise, the reclusive Douglas Iris which we planted in December opened its blossom as the sun shone on it towards noon.   Our labors produced a number of bags of weeds and a re-opened path to the upper beds. We also had an outpost worker with a weed wrench who went to the higher, sunnier elevations and pulled the several broom plants which were lurking in the sunny spots waiting to produce seed.

A small contingent of Earth Day workers got a special pass to avoid weed pulling and to help Bob Brodersen locate and GPS map the oak forest in Garber.   This important knowledge will help us and guide us through the park for next week's Sudden Oak Death (SOD) BLITZ.  On the way to one of the remote sites, they flushed a red fox!! who took off promptly after being disturbed.  Undeterred, Bob and his helpers finished the mapping.  IF YOU WISH TO HELP OUT WITH COLLECTING SAMPLES FOR THE BLITZ, CONTACT US RIGHT AWAY at garberparkstewards@gmail.com.   We know that the infection is present in Garber.  It has the potential to kill a majority of the oaks in Garber Park.  

Click here for more pictures of Earthday in Garber

Citizen Science Workshop: Sudden Oak Death: Strategies for Facing the Pathogen in Garber Park

On April 7, the Garber Park Stewards were pleased to host a Citizen Science Workshop focused on Sudden Oak Death, presented and led by Lech Naumovich, Ecologist, of the Golden Hour Restoration Institute.

Well-attended by naturalists, arborists, landscapers, trail workers, and interested citizens, the workshop provided in depth instruction and commentary on the current state of research and understanding about the disease. Click here for a PDF of Lech’s excellent 4 page handout on SOD resources.  In some ways more compelling than an update on the research, this workshop provided hands on and eye witness evidence of the existence and the material indicia of SOD infection in the oak forest of Garber Park.

It is one thing to look at photographs of the pathogen and its effects on living forests, but it is quite another to recognize the characteristic bleed of an infected tree right in front of you.  Perhaps counterintuitively, the pathogen slowly and methodically kills an oak tree by girdling the main stem.  Looking directly at this process, you cannot avoid an increasing appreciation of the complexity of the SOD blight in the landscape that surrounds you. Even the ground breaking research of Matteo Garbelotto’s UC Sudden Oak Death Lab does not suggest a strategy for “saving” a forest under attack.

The pathogen itself is a recent (within the last 20 years) stowaway on nursery stock (probably rhododendrons) and within its own biological limits has spread rapidly into Northern California backyards and forests which are evolutionarily unprepared to fend it off.  The bleed on an infected oak is evidence of resistance in the victim, but the functions of immunity are poorly understood to date. The highly vulnerable tan oak forests of Marin County exhibit a mortality rate over 90% while the Coast Live Oaks exhibit only 55% mortality—perhaps due to innate or developing immunity.  Currently available chemical treatments aim to boost the immune response of particular trees in order to save them. But a forest is a great deal more than a de facto gathering of particular trees.

In the complex riparian woodland of Garber Park, each of the four constituent trees (and many shrubs) is affected by the pathogen.  The Big Leaf Maple and the California Buckeye are passive carriers.  The pathogen aggressively feeds on the leaves of the Bay Laurels without killing the tree and the Bay Laurels serve as a vector for the conveyance of the pathogen through the forest.

The Coast Live Oak appears to be an unintended victim and a dead end for the pathogen.  An infected oak has not been shown to transmit the pathogen to another host. Yet, the possible consequence of 55% mortality of Garber’s Coast Live Oaks is a circumstance of great magnitude from every point of view including the loss of mature canopy and fire hazard that would exist from numerous downed heritage oaks.

As the Workshop demonstrated, there are no solutions or prescriptions at this time for “saving” an infected forest, though there may be ways to “save” an infected tree.  Deepening research and increasing experience of arborists may hasten the time when there are proven strategies.  But there are many things we can do now as interested individuals and groups.  We can support the work of the SOD Lab by participating in the upcoming SOD Blitz at the end of April.  The Garber Park Stewards are using the SOD Blitz to better assess the rate and range of infection exhibited by Bay Laurels.  Using a grid system we will collect apparently symptomatic leaves and submit them for testing.  The results will be available in October. 

Sign up now to help with the SOD Blitz 2012 on the weekend of April 28-29 Attend a one-hour long training offered by U.C. Berkeley Dr. Matteo Garbelotto, and then collect symptomatic bay leaves.  Return samples to a drop box at the training site by Sunday evening. To sign up for the UC Berkeley training, go to http://sodblitz2012.eventzilla.net.  To help in Garber Park contact garberparkstewards@gmail.com

We can hone our understanding by recognizing the pathogen and closely observing its operations in Garber Park’s forest.  Phytopthera ramorum is an invader which may become endemic. Whether by direct intervention or more passive strategies,  it behooves us to do as much as we can to spare our native landscape the worst effects of this pathogen.

SEVENTH GRADERS MEET NEWTS AND CAPE IVY

For our regular first-Tuesday workday in April, the Garber Park Stewards and our Botanist, Lech Naumovich, were happy to host about 20 Head Royce seventh graders and their instructors,  and happier still to extract from them two hours of labor in the meadow pulling cape ivy.  We set up three work sites with tarps for collecting the pulled stems, and we stood back and let them at it.
They pulled and pulled, found a newt,  pulled some more, and had a contest to see who could pull the longest stem, and pulled some more, and bagged the piles of stems, and carried the bags to our collection point.  

They also found out that the cape ivy in the meadow covered up a lot of things including lots of blackberry plants, both native and Himalayan--they both have thorns--and stinging nettles, and giant vetch which is in bloom right now, and lots of oddly segmented horsetails just high enough now to assess how high they will have to get in order to rule the meadow this summer.  Six feet probably.  In the end 20 Head Royce seventh graders can make quite a dent in cape ivy.  
We had fun, we pulled cape ivy, and we want those seventh graders back for an encore performance. There are still great expanses of cape ivy left to vanquish.
For more pictures click here.