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Posts Tagged ‘ecology’

by Andrea Williams

This is installment six of a 12-part series on grasses. Read the previous installment here.

Even though I’m a cat person, every February I love to watch the two-day spectacle of the Westminster Kennel Club Dog Show. I’m just a taxonomist at heart, and I enjoy spotting the subtle differences between the American foxhound, Harrier, and English foxhound; or how the different groups came to be and why the Non-Sporting group is such a mish-mosh of breeds. But there are also the subtle cautions offered by announcer David Freese that make me think of gardening: Know your breed and pick the one that’s right for you, and don’t buy into the “fad” or “popular” breeds (e.g., dalmations after “101 Dalmations” came out, or whatever breed wins the WKC). And that brings me to pampas grass (Cortaderia sp.).

Jubata patch in slide area off Hoo-Koo-E-Koo on Mt. Tamalpais

Jubata patch in slide area off Hoo-Koo-E-Koo on Mt. Tamalpais

California’s pampas grasses are two very similar-looking but reproductively different species, and just like irresponsible breeders can churn out sick dogs to capitalize on a fad, irresponsible or ignorant plant breeders can inadvertently introduce pest plants or diseases in trying to create or capitalize on a fad. According to this excellent article in the 2004 Cal-IPC news, pampas grass (C. selloana) was originally brought up from the South American pampas for its striking inflorescences. The white, fluffy plumes are only produced by the female plant; the male plant’s plumes are darker and thinner. So for a while, only female plants were planted and exported, and no spreading could happen without the males. But fads catch on, and inevitably the male plants made their way into the world, as did the similar-looking purple pampas grass (or as I prefer to call it, jubata grass, C. jubata). Jubata grass, nearly opposite the outcross-dependent pampas grass, is apomictic—seeds form from the female ovules without fertilization. This allows it, like the also-apomictic and wind-dispersed dandelion (Taraxacum officinale), to establish new colonies over long distances and take advantage of disturbances.

Most of what we have in Marin is jubata grass; proper pampas grass is mostly strictly coastal, and found in San Mateo and Southern California (although the Richmond-San Rafael Bridge corridor is an excellent spot to see both species side-by-side). Because of its need to outcross, pampas grass can be slower to establish since the winds of chance need to blow both male and female plants within pollination distance. But that also means it may be able to adapt to changes and eventually invade more areas. The hare to pampas’ tortoise, jubata grass quickly covers disturbed and difficult-to-reach sites such as roadcuts and landslides. We try to keep on top of our populations on Tam, and have managed to mostly keep it contained in a few sites and prevent seeding. The good news is, although the seeds are numerous and far-slung—over 1,000,000 per plant traveling many miles on the breeze—they are short-lived, usually only a year. So once the adults are treated and re-invasion of bare ground is minimized, the follow-up is minimal. Better, though, if we’d had an ounce of forethought and prevention a century ago, and not introduced such an aggressive breed.

Don’t plant a pest: Ornamental grasses of the Bay Area region (California Invasive Plant Council)

An aside/post-script: Speaking of capitalizing on fads, a recently invading ornamental (Erigeron karvinskianus) that used to be called “Mexican fleabane” is now being called “Santa Barbara daisy” and people are buying and planting thinking it’s a California native … which it’s not!

 

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by Eric Ettlinger

Coho smolt

Coho smolt

Salmon in California have evolved to follow the seasonal rhythms of wet and dry periods as they migrate between their natal streams and the ocean, and then back again. The fall rains that swell Lagunitas Creek and herald the return of adult salmon to Marin County also encourage young coho salmon to begin their downstream journey to the ocean. In normal years, winter is the time when many of these young salmon migrate from headwater tributaries down to lower Lagunitas Creek, where they transform into silver smolts in preparation for the ocean phase of their life cycle. These smolts wait in the lower creek until April and May before entering the ocean, just in time to take advantage of the spring plankton bloom.

2013 and 2014 have not been normal years, however. Fall rains were infrequent and light, and January was the driest on record. The drought caused a significant delay in salmon spawning and resulted in a much smaller coho run than expected. The extended dry period did, ironically, seem to benefit the young salmon preparing to emigrate to the ocean. Many coho fry were unable to migrate downstream until the rain finally arrived in February, which meant that they weren’t packed together in lower Lagunitas Creek. The habitat in the lower creek can’t support very many young salmon through the winter, which appears to be one of the principal factors limiting the size of the entire coho salmon population. This year, salmon fry spent the winter spread throughout the watershed, and likely spent little time crowded in the lower watershed.

The result was the largest emigration of salmon smolts yet seen in Lagunitas Creek. Biologists with the Watershed Stewards Project, the Marin Municipal Water District, the National Park Service, and the Salmon Protection and Watershed Network counted coho smolts every day between late March and early June as they migrated past traps on Lagunitas, Olema, and San Geronimo Creeks. In typical years the lower watershed doesn’t appear to be able to support more than approximately 11,000 juvenile coho salmon through the winter. This year nearly 20,000 coho smolts emigrated to the ocean.

smolt chart

Click the image above to view full-size chart

What does this mean for the future of coho salmon in Marin County? In the short term, if food is abundant in the ocean we could see 2,000 adult coho return to Lagunitas Creek in 2015 (the most in more than half a century). On the other hand, this year’s smolts were fairly small and may not survive well. Over the longer term, while we can’t recreate this year and prevent coho from migrating to the lower watershed, we can provide more habitat there. A grant currently being considered by the California Department of Fish and Wildlife would fund the construction of five projects in lower Lagunitas Creek to expand side channels and floodplains for coho salmon winter habitat. Hopefully this grant will be funded and the projects will achieve their goals. As with the seasonal migrations of salmon, we’ll just have to wait and see.

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by Andrea Williams

This is installment five of a 12-part series on grasses. Read the previous installment here.

blue wildrye

Blue wildrye (Elymus glaucus)

I know I should like American robins, but I don’t. It’s just that they’re so common. And I kind of feel that way about blue wildrye (Elymus glaucus).

I first learned blue wildrye in Oregon, during those formative summers on a coastal grassland overlooking the mouth of the Salmon River. Being new to grass ID, I really appreciated how obvious it was—four-to-six-foot-tall spires in a foot-wide clump, usually a bluish-green color with short upper blades flagged straight out from the stem. The inflorescence was nice and simple, too, a narrow, bristled spike. No branching, or sterile florets, or measuring or counting veins to worry about. Just blue wildrye, plain and simple. And then I started monitoring grasslands, and I was so over blue wildrye.

Because it was everywhere. So common. And easy to collect, and easy to grow. Just bend the flowering stalks into a bag and “milk” the seeds and the ripe ones slide right out. Then scatter the seeds over a site and next growing season it will be lousy with wildrye. And these are all good things. Like robins. Sharp red breast, jaunty hop, cherry-dew song. But they’re everywhere. So common.

And so it is sometimes: The need for the new, the value we give to rarity overshadows the basic merits of a thing. I just have to remind myself to appreciate and celebrate the common, to see with new eyes instead of wanting my eyes to always see the new.

 

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by Andrea Williams

This is installment four of a 12-part series on grasses. Read the previous installment here.

California oatgrass

California oatgrass (Danthonia californica)

I’m sure you’ve heard the phrase “sowing your wild oats,” but did you know that California wild oats (aka California oatgrass, Danthonia californica) is the grass that loves you back? And they have a secret seed to sow?

I grew to know California oatgrass in Oregon, when I spent my summers on a coastal grassland studying the habitat of the threatened Oregon silverspot butterfly. At first I just liked how obvious it was, three fat spikelets and a little eyelash winking at you where the grass blade met the stem. It wasn’t until my time at Redwood National and State Parks that I appreciated the ingenious strategy this grass employs in reproduction. And it wasn’t until last month that I fully appreciated just how hardy and long-lived California wild oats can be.

Most grasses, California oatgrass included, reproduce through wind-pollinated flowers that turn into seeds; think wheat or rice grains. But oats, California oatgrass included, are tasty and can be browsed down before they have a chance to become a new plant. California oatgrass has a contingency set of seeds in the base of its flowering stalk. These flowers are cleistogamous, meaning—like nuns in a cloister—they are kept shut away. The flowers self-pollinate inside the stem, and when the upper (chasmogamous, opening, like a yawning chasm) wind-pollinated flowers have ripened into seeds and are ready to drop, the stem itself detaches from the basal clump of leaves. This gave rise to a new dance, the “Danthonia Shuffle,” during a native grass seed gathering expedition. Rather than plucking individual seed heads, you can shuffle your feet through an oatgrass-laden path and once a sufficient number of stems have gathered around your shins, just scoop the whole lot up into a bag! You not only have the seeds that haven’t dropped from the seed heads, but you have the straw and the secret seeds as well!

California oatgass secret seed

California oatgass secret seed

California oatgrass, once established, is a hardy and forgiving plant that tolerates mowing well. It does prefer wetter areas in grasslands, where it mixes with purple needlegrass, blue-eyed grass, and the cheery yellow of California buttercups. On Mt. Tamalpais, our oatgrass tends to have three to five spikelets above a clump of slightly greyish green leaves. On the coast, plants tend to be a little greener. Last month, as I was staffing the California Native Grassland Association booth at the Point Molate Beach opening, I looked down at the mowed-and-trampled ground and saw a little oatgrass eyelash winking up at me from an emerald clump of leaves—California oatgrass had survived decades of people walking and mowing and picnicking and parking on it.

And why is it the grass that loves you back? The arrangement of spikelets matches the hand symbol for “I love you” in sign language.

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by Charlene Burgi

Spiders and snakes seem to be a topic of discussion these days. The conversations are not about a resurgence of the 1970s Jim Stafford song “Spiders and Snakes,” but about the legless and eight-legged varieties. Is it any wonder that this subject would come up? Spiders and snakes emerge during the spring, and thus we are seeing more of them right now. Unfortunately, these encounters tend to conjure up stories better suited for campfire talk than for encouraging our friends to invite them into the garden!

Fear of these reptiles and arachnids seems to cloud the fact that they are a benefit to the garden. Neither will be found eating your favorite pansy, digging up your garden, or girdling woody stems with sharp teeth. On the contrary, they are in the business of eliminating garden nuisances such as rodents, slugs, insects, and soft body scales in the garden. Yet people of all ages tend to panic at the sight of either!

I must admit it is a bit startling when, out of the corner of your eye, you see a snake slithering toward you, or when you reach in for a ripe tomato and encounter a beautiful black and yellow garden spider known as Argiope aurantia. But though that first meeting can be a bit alarming, these are not invaders to eradicate but visitors to encourage.

Enticing reptiles, including lizards (think of them as snakes with legs), to live in the garden requires very little work on your part. They hibernate underground in the winter, so a stack of flat rocks would be an ideal habitat for them. Snakes are cold-blooded and what better place can you offer to these sun lovers?

For the most part, snakes have a shy, retiring disposition. They prefer hiding in nooks and crannies rather than putting themselves in the harm’s way of an overhead hawk, prowling dog or cat, or ill-informed gardener that sees threat instead of friend. We don’t realize the fear snakes have of people lurking around in their habitat. If you encounter a snake, stand still and you will see it retreat to a safe place.

Garter snake next to pile of rocks

Garter snake

This past week, the pups and I were in the backyard when, next to some stacked stone, the yellow racing stripes of a beautiful garter snake (Thamnophis) caught my attention. The pups lopped forward unaware of the snake, but the snake took no chances and retreated into the safety of the nearby rocks. I was delighted to see him, but made a mental note to offer more protection if Sassy and Misty decided to investigate further at a later date.

People also have a fear of spiders. In spring, it is typical to find them both inside and outside of our house. While I don’t appreciate living with them, it is common to find Jack or me trapping them inside to release back outdoors. They will eat a lot of bugs! It is interesting to note that 60% of spiders capture their prey in a web, while 40% are hunters. The hunters are active in the garden that is heavily mulched and laden with just the right type of juicy insects to sustain them. Either type of spider will help clean your garden without worry of doing additional damage to foliage. Put the case of arachnophobia aside and rejoice in the benefit that spiders bring.

Before I close, I would be remiss if I didn’t acknowledge that there are a few—very few—poisonous snakes and spiders in our area. Both will avoid you if you leave them alone. Black widow spiders are typically found in dark, damp places like wood piles and water meter boxes. Proceed with caution when working in these environments or similar places. Rattlesnakes are typically found in areas similar to where harmless snakes venture, but remember that they are as shy as the harmless snakes and will first let you know you are invading their space with a shake of a tail. Give them room and they will depart from your presence.

The not-so-warm-and-fuzzy things in the garden can be more of a benefit than the warm and fuzzy—like rabbits and squirrels, gophers and deer. And, contrary to the chorus from Jim Stafford’s song, I do like spiders and snakes!

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by Andrea Williams

This is installment three of a 12-part series on grasses. Read the previous installment here.

Last month I talked about California’s state grass, purple needlegrass (Stipa pulchra, formerly Nassella pulchra). This month, California’s state rock, serpentinite (although we usually just call it serpentine since it’s made up of serpentine minerals), takes center stage. California was actually the first state to designate an official rock, but serpentine is special and, like our Mediterranean climate, helped give rise to plants found nowhere else in the world.

barbed goat grass

The spikelets of barbed goatgrass look a little like goat heads, although that’s not where the name comes from.

Because of the makeup of serpentine rock, and its slow weathering, serpentine soils are thin, poor, and high in heavy metals. The mineral balance is quite different from what most plants can tolerate, so many plants found on serpentine are endemics: they’re only found on this soil type. Others can grow on serpentine and non-serpentine soils, but may be stunted or appear different when living in the strange soil.

Many weeds take advantage of disturbance and can quickly use resources, outcompeting other plants. But serpentine’s qualities make it naturally resistant to invasion, with a few notable exceptions. That brings us to this month’s grass: barbed goatgrass (Aegilops triuncialis). Originally from serpentine soils in the Mediterranean region and Eastern Europe/Western Asia, barbed goatgrass can thrive in our soils and climate. Not only does it do well on serpentine, the high silica content of the litter it produces is difficult to break down, further altering the soil and making it even harder for other plants to grow! Goatgrass also has a built-in seed stashing strategy: Each spikelet generally has two seeds—one germinates the first year, and the other lays dormant for a year—so even if you get all the plants in a year, the seedbank of this annual has a surprise waiting for you the next.

habitat restoration site

On May 17, help pull invasive barbed goatgrass in this beautiful spot.

Nearly half of our rare plants are found on serpentine soils, which makes these areas so important to protect. You have an opportunity on May 17 to help remove invasive barbed goatgrass from serpentine soils on Mt. Tamalpais, in the Azalea Hill/Pine Mountain area. We’ve been pulling goatgrass from this site for many years, and stemming the tide of invasion. Nine different rare plants call this spot home, and jackrabbits and kites are often seen as well—not to mention our state flower, state bird, and state rock!

 

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by Andrea Williams

This is installment two of a 12-part series on grasses. Read the previous installment here.

California state flag

California state flag

You all know the grizzly bear is a main feature of the California flag, but did you ever give a thought to the turf below its paws? While I can’t be certain, I and others like to think they are tussocks of our state grass, purple needlegrass (Stipa pulchra, formerly Nassella pulchra). Did you not know California had a state grass? Purple needlegrass was designated our state grass in 2004, so while it’s only been official for 10 years, this pulchritudinous pastoral plant has been an important and widespread part of our state since well before there was a California. In fact, since individual purple needlegrass clumps can live more than 150 years, there may be plants alive today that have been around since before there was a California!

purple needlegrass

Purple needlegrass (Stipa pulchra) Photo credit: Stephanie Bishop

Purple needlegrass is not only widespread and long-lived, but also quite distinctive in its look. Its inflorescence of delicate purple pennons wave above a mound of fine emerald blades. This fine look has it also available at many native plant nurseries. Some may mistake ripgut brome (Bromus diandrus) for purple needlegrass, but the former—a non-native annual weed—holds a fistful of red bristles on single stalks, with no basal clump of leaves. And while ripgut brome is a danger to grazing animals, purple needlegrass remains an excellent forage species—for cattle, elk, deer, or bears!

 

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by Eric Ettlinger

Coho season is wrapping up, and thankfully it’s ending with more of a bang than a whimper. In late January, at the typical end of the coho spawning season, the San Francisco Chronicle ran the headline “Crisis for the coho” with a couple of pictures showing the extremely dry conditions in the Lagunitas Creek watershed. As if on cue, the rain started falling a few days later and coho spawning took off. Since then spawning activity has subsided and in the last week we’ve seen what are likely the last few coho of the season. Our preliminary watershed totals are 433 coho and 203 redds, which is roughly double the size of the coho run three years ago.

Steelhead (pictured) have also been spawning in impressive numbers. In the last three weeks MMWD biologists have seen 153 steelhead and 126 redds. Steelhead are likely to continue spawning through at least April, and at this pace we’re looking at a very good year for steelhead. Rain is forecast to return late next week, which should bring up another wave of steelhead spawners.

steelhead female and small male

Steelhead female and small male

steelhead male

Steelhead male

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by Andrea Williams

This is installment one of a 12-part series on grasses.

When someone asks what my favorite grass is, I prevaricate. Who can have just one? If pressed, I’ll pick California oatgrass (Danthonia californica), for reasons I’ll get into another time—but as a genus, fescues (Festuca sp.) are the best. Several of them have made their way into our gardens as lawns and ornamentals, but they’re natural standouts.

Most of our native fescues like to grow in big tussocky stands, sending slender stalks of spikelets to wave above dense clumps of fine leaves. Idaho (or blue) fescue (Festuca idahoensis) is probably our most well-known native; the tight blue bunches accent many a drought-tolerant landscape, and it’s found in our hottest driest spots on Mt. Tam as well. In the wild, it’s a little looser and tends to silver instead of blue, and can be hard to tell from red fescue (F. rubra) on occasion. Red fescue’s leaves aren’t red, but its flowering stalks often are. The fine leaf blades are rolled in long needles, and in most cases are a deep emerald green—the exception being, of course, when it grows in drier spots with Idaho fescue and the two species are almost indistinguishable. Red fescue is at its finest on the coast; the most common cultivar ‘Molate’ is from Point Molate, just on the Richmond side of the Richmond-San Rafael Bridge, where the coastal grassland was nearly lost to development.

California fescue on Azalea Hill

California fescue on Azalea Hill

Our largest and perhaps most striking native fescue (or fesque, as it used to be spelled) is California fescue. Clusters of blue-green leaves grow as tall as three feet and tussocks can reach four feet across; single flowering stalks reach six or more feet in the air. The plant keeps its flowering stalk and stays mostly green year-round, keeping things visually interesting as the seasons turn. I usually find it at moist edges of woodlands and forests, and the stands near Azalea Hill and along Bolinas-Fairfax Road are some of the finest anywhere. Sometimes people have difficulty telling California fescue from the thirsty fungus-harboring invasive non-native tall fescue (F. arundinacea), but the coarse broad green blades and tillering spread of tall fescue are dead giveaways.

So whether you’re seeking a good-looking grass for your yard or on a hike, just remember: it’s fescue to the rescue!

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by Eric Ettlinger

Female coho

Female coho (photo by Rosa Albanese)

It’s been an exciting couple of weeks in the Lagunitas Creek watershed. In my last update I described how coho salmon spawning had unexpectedly jumped up (so to speak) following a tiny bit of wet weather on January 30. Another small rain event followed that survey, coinciding with an increase in water releases by MMWD, and more spawning ensued. Over three long and wet days last week MMWD biologists surveyed most of Lagunitas Creek, and finished the uppermost section of creek this morning. In total we counted 118 coho salmon and 56 new coho redds. We also counted 118 salmon during the previous week, but it’s difficult to say how much of this coincidence was due to counting the same fish twice. To date we’ve seen 349 coho and 161 coho redds. This is an increase over three years ago, but still far less than the large coho run we were expecting.

The other big news was, of course, the enormous amount of rain we received. Since Friday the Kent Lake rain gauge has recorded over 11 inches of rain, while the gauge at the top of Mount Tamalpais recorded over 21 inches! This has helped our water supply situation and has finally allowed salmon to swim into the tributaries. Flows are still too high and turbid to conduct surveys, but later this week we’ll be investigating how many salmon survived both drought and flood to return to these creeks at last.

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