Showing posts with label invasive plants. Show all posts
Showing posts with label invasive plants. Show all posts

Saturday, April 25, 2020

How Do We Go From Here



The plants know, nine times out of ten, the right time to leaf out.  As warm as it is, as many days as it has been, those plants ill-equipped to fight off a hard freeze have survived by delayed emergence.


Many plants developed strategies for managing cold at emergence; the delicate appears tough. A dose of anthocyanin may (or may not) inhibit freezing water within young leaves of columbine.


Garlic mustard in the lowlands, where the soils are wet, show significant purple coloration where the mesic, upland colonies do not. Those in the lowlands are often frost heaved, repeatedly, as the late winter progresses to early spring. This is the best time to pull lowland garlic mustard as the frost heave aerates the underfoot, easily compressed wet soil.


There is no shortage of venturesome Old World garden plants. Besides England's Creeping Charlie, which appears to grow at length under the snow, there is Russia's loved Siberian Squill, above. Lamium maculatum is found in all corners of the world and our woods. Later in our season, the European Bellflower and Eurasian oxeye daisy. The problem isn't from whom or where these came, but how to manage what we must live with, now that it is here.


Iris reticulata, planted last November. Could these little beauties be just as versatile and productive as those already mentioned? Does the mature gardener ask why certain plants are necessary; do they seek out only those from a New World palette? How do convenience, apathy, desire, culture inform our choices? For each choice there are positive and negative consequences, understood and misunderstood. What strategy do we have for making good decisions among so many emotionally ambivalent and intellectually challenging choices?


We have choices, but can make only one decision. Who's in that four jet plane, traveling well above my head? Are there five people aboard, or three hundred? Do we need to fly, should we tour the world? Who are we if we stop? We won't stop.


The sun sets late now. It has been dry, very dry, with no appreciable rain in weeks. I notice the sunlight on an oak twig shaken free by windy days.


Plastic laid on the septic slope to solarize the weed field it has become.


I take a lap around the house, stopping to notice the lattice rehab I recently completed. Framed by the rose trellis, I do not see the house as much as I see all the projects I have done.

1. Railing rehab 2. Build new railing 3. Jack up porch to attach new posts to concrete piers 4. Rebuild lattice 5. Replace sheathing, reside and paint 6. Build new, but lower, deck 7. Replace rotten door sill and and rotten door 8. Solarize creeping charlie, regrade, and install sod 9. Move climbing roses out of shade 10. Remove hydrangeas from south side of house and replant as a hedge along the driveway 11. Frame raised beds with cedar boards and add chips 12. Remove and replace rotted deck boards.




The house lapped, I pause to look at the lattice rebuild in the back. The setting sun warms the old pink still present under the porch, setting off the grey we chose to replace it.



Wednesday, July 3, 2019

The Slough


A busy life, the return of mosquitoes and then the ever more aggravating deer fly, have kept me from the woods -through which I must pass to get to the back slough. The slough, a small natural woodland basin bordered on its west by an old gravel pit, has become wetter over the last decade. Prior owners of the neighboring pit decided it would be more useful filled and so introduced a stream of trucks dumping their fill.  We believe this raised the water table and is the reason our woodland vernal pond supporting silver maples and green ash has become a permanent swamp; one that has dried, only temporarily, a couple of years out of ten. The last of the trees within its bounds has died and the aggressively spreading, wet soil tolerant canary reed grass has taken hold in the newly sunny slough.



Yesterday morning a meso-scale storm passing just to our north provided a strong draft and mosquito-free window to pass through the woods. The last time I gazed upon this rapidly changing two acres it was a pond pushing beyond its bounds. Now, the lower water table of summer has changed it to a burgeoning meadow; the remains of duckweed sitting on a crust of drying muck.


Phalaris arundinacea
Canary Reed Grass, Phalaris arundinacea
Although I seeded a portion of the slough in December with what is called a detention mix, I'm not surprised to see an abundance of human-bred, hybrid canary reed grass, Phalaris arundinacea.



It is a surprise to see the blue flag, Iris versicolor, I planted two years ago continuing to bulk up, maybe even thrive, despite the competition from so much mad dog skullcap, Scutellaria lateriflora.



This sedge, "weeded" out of a wetland edge of a nearby lakefront residence, has begun to transform the northwestern edge of the slough. I hope to see it "make a stand" against the encroachment of canary reed grass.

I purchased seeds of another grass, prairie cord grass, but have been hesitant to distribute the seeds. It is a native, warm season slough grass that I intended to use as a foil to the cool season canary reed grass. Like canary, it spreads by rhizomes and can be aggressive. Although it grows all over Minnesota, further reading led me to think that the six to eight foot grass may not be the right choice. I'd rather be out ten dollars in seed than dealing with another grass, not currently present, that then spreads too widely. My curiosity, however, gets the best of me -I have tray-seeded a few to see how they grow.



As more storms approached from the north, I pressed on toward the little wetland to see how it has changed since the high water of late spring. Water sheds from the surrounding moraine, draining through two gullies, then filters through two wetlands to pool at the bottleneck that leads to our driveway culvert. Earlier this spring I cleared the growing stand of buckthorn from the floodplain surrounding the bottleneck. Dying ash and falling box elder have opened the canopy here, letting in more sun.


In early June I made an attempt to slow the spread of canary reed grass weakened by five weeks of flood waters. Wearing knee high rubber boots, I cut any grass growing along the perimeter of the open water with a weed trimmer. Although it has come back now that the water has receded, it has done so less vigorously -a rather minor victory. If I want to maintain open water here, or better yet, introduce sedge and other wetland plants, I'll need to continue to fight back the canary reed grass which has a stranglehold on much of the small wetland.



Last Saturday I spent an hour at a nearby natural landscape contractor's end of season native plant sale. Most of my purchases (only $2.50 per plant!) were infill for my prairie plantings, but I did buy a couple of wetland plants. Above, ironweed, Vernonia fasciculata, has a wetland indicator status of facultative (FACW). This means it usually occurs in wetlands -66 to 99 percent of the time. This wetland status and my failure to grow it successfully in my dry Brooklyn garden led me to choose the flood plain as its new home.






My other purchase, broad-leaved arrowhead, Sagittaria latifolia, has a wetland status of obligate wetland (OBL) which means that it occurs in wetlands nearly 100 percent of the time. This plant prefers standing water and at least partial sun, so I placed in the pool that collects at the bottleneck, a stones throw from the ironweed.

We've been in a very wet period, receiving several inches of rain over the last two weeks. The tropical air and daily storms are expected to last through the week. Over the last 24 hours we've received over 3 inches of rain, and another three plus within the last ten days, bringing the water table back up to where it was in late May. This morning, braving the mosquitoes, I ventured to see the arrowhead I planted two days back -but it is missing, most likely it has tipped over into the muck under the rising water.


Tuesday, December 4, 2018

Winter Seeding


Our first snowstorm was brewing on top of an inch that had fallen two days prior. Although there was much to do, I paused to get out to the back swale, once wet, now dry, to scatter the seeds I had collected.


The roughly two acre swale, either artificially created by gravel mining just over the property line or an artifact of the terminal moraine on its northern flank, used to dry up each summer, enough so that tree species accustomed to periods of water logged soil could still grow to sixty or seventy feet tall. These trees have now died, the largest within the last three years, because of permanent inundation.

This year, another change had taken place -the swale dried down. The spring tree which drains the area continues to flow and a walk through the swale could still leave you suctioned to its wet bottom, but the hummocky surface is dry, the duckweed a gray mat. With that had come an incredible explosion of canary reed grass, the cool season, hybrid grass created for just this type of environment. In two short months the grass multiplied its square footage by ten and left little room for intervention by this woods gardener.


Canary reed grass or reed canary grass, Phalaris arundinacea, is terribly hard to remove -more so than garlic mustard, buckthorn, and creeping charlie combined -for its wet soil, its nearly impenetrable mat of fibrous roots, its rhizomes and seeds. Although developed for haying wet ground, wild animals do not care for it. Yet here, it is clipped, but I cannot recall whether I clipped it in preparation for some type of management or it has been grazed by deer this late autumn. If it was deer, that would be unusual.


I will not be able to remove the reed grass, nor do I intend to spray glyphosate on it. I've tried plastic tarps, but there are now too many woody obstructions over a region much too large for that. My plan is to seed this open area, ahead of the advancing grass, in hopes of some species gaining a foothold. Only if the pond does return, to its last maximum, will the open water push the mat of grass back to its edges.

If the pond does not return, this wet meadow may have a limited number of species capable of growing alongside canary reed grass. I've seeded blue vervain, Verbena hastata, common milkweed, Asclepias syriaca, swamp milkweed, Asclepias incarnata, various asters and goldenrod, and a bit of big blustem. I had two dozen blue lobelia, Lobelia siphilitica, starts remaining from the late summer planting, roots still alive, that I dropped in the hummocks under the snow. And in late September I planted dozens of Spotted Joe Pye, Eutrochium maculatum, more blue lobelia, and several other species I cannot recall at the moment along the more shaded swale edges where the canary reed grass had yet to overtake.








Saturday, August 11, 2018

In Stillness and Warmth There is Mosquito

On an unusual summer day I come to fully appreciate how little I venture into the hot season woods. Like winter, or maybe more so than winter, the summer time woods belongs to others. But on those two days, when temperatures plummeted into the fifties by night, only the sixties by day, with a supplementary breeze from the northwest, the woods invited my eyes and skin as if it were a day in early May or mid October.



Few mosquitoes made a stroll of getting to this laetiporous in the once wet middle slough.



How little I experience the woods in summer dictates my familiarity with its cycles of growth and senescence. On this walk I was thrilled to find plant species I have yet to see here, more vigorous growth than in the past, and less encroachment by aggressive species in some places. This could have been my own doing, attributable to three years of pulling garlic mustard, or was it the longer, cold winter that favors those that have evolved with it?

What I have experienced this year, one too busy with other activities to commit to the two month long pull, is roughly a ninety percent reduction in garlic mustard seedlings and a nearly one hundred percent reduction in second year rosettes. Why is this? Although it is tempting to enjoy the reprieve, it is more helpful to understand the process. Has our pulling had an effect? Or was it the temperature and frozen ground through out April (garlic mustard is some of the earliest of greens)? Is there a natural rhythm to biennial growth that gives way to an unproductive season?

This is not to say that there is no more garlic mustard in the woods, there is. A few lush, large-leafed specimens grow around the water line among large patches of Pilea pumila, clearweed, a native annual that sprouts in the heat of summer. Without the garlic mustard cover, it has been able to rise up from its own large bank of seeds in areas dominated by garlic mustard for years. Even the small patches of first year seedlings on barren slopes seem to be the exception proving the rule.


The swamp in the back has largely drained for the first time in three or more years. It is now a topography of muck covered in still-green duckweed shifting toward brown, nearly perfect growing conditions at the old waterline. The low water means we do not host wood ducks that have been in residence since we've moved here. The changing shoreline, three years wet, another dry, has created challenging conditions for almost anything, trees included, that isn't the nearly ineradicable reed canary grass, Phalaris arundinacea. If you do not know this plant, then it is likely not in your neck to the woods, yet. In the upper Midwest, where it is likely there are more pothole wetlands than anywhere else in the nation, it is still being planted as a wetland "forage" grass to make "useful" what was once too wet to grow anything a farmer might describe as useful.



Growing on the edge of the swamp: Pilea pumila, Leersia virginica, a few Bidens spp and Impatiens capensis
I was delighted to see these patches of healthy growth along the eastern swamp edge where the water line has receded. Now that the trees have died from inundation, more light enters here, giving a greater diversity of plants a shot at growing.


One of those plants is mad-dog skullcap, Scutellaria lateriflora.



Only a few stems and rhizomes at the edge of high water late last season, this mint is now such a prolific grower that, if I knew less, would think it could compete with reed canary grass. It is known to take advantage of disturbed sites, whether made or naturally occurring (this site is arguably human-altered). Although some have nosed out above the mad-dog, it has handily out-competed last autumn's planting of joe pye, iris versicolor, big bluestem, cardinal flower and verbena. Yet I accept this because, pause...it is a native.


 
Why is that? After all, ignorant of its origins, I might think this grass is doing a great job of greening up a mucky swamp of dead trees. It's the analysis that triggers concern, the conceptualization of homogeneous communities that also send up red flags, and maybe an aesthetics of bio-diversity that has me lurch into action.



That action can take the absurd form of a twenty by ten foot plastic sheet. Placed last summer to smother the reed canary grass, yet appears to have only made it stronger. Once the grass takes on these proportions it is impossible to eradicate by hand pulling. The dense mat of roots and rhizomes have such a tenacious grip that standing in the muck pulling on it produces a feeling of futility and a frustrating clump of leaves in hand. In placing my efforts elsewhere I may have to accept that what was once a forested vernal swamp is now, in wetter times, a clearing, an occasional pond, and quite soon a reed canary wet meadow.



Just up slope from the reed canary grass and mad-dog skullcap is a mighty patch of the weedy Canada thistle, Cirsium arvense. Whereas reed canary grass provides little support for other creatures, Canada thistle at least offers food for pollinators and birds. 



Despite the near drought conditions (you can still have one even when there are occasional heavy thunderstorm rains) that led to drying of the back swamp, water is flowing more heavily than is typical from the spring tree. Why is that? I have seen high water in the swamp with much less flow from this seep, only fifty feet from the swamp and about the same elevation, if not a few inches lower.



The spring tree seep is the only year-round flowing water in our woods, typically runs orange with oxidized iron fixed by iron consuming bacteria. Perfectly natural.


For us "coasters," where certain introduced insects, aquatic organisms, and plants have been around for generations, our relationship to them is different. Can you imagine the idea that Queen Anne's lace is an upcoming threat? How about the notion that your garden is suffering a never seen before invasion of Japanese beetles? Although some species are new to the area, plants like buckthorn have been spreading from yards and nurseries for long enough that a generation or two do not know what the woods looked like without it. In this slippage change becomes fixed and the concept of paradise is born as a way to process that faint, nearly imperceptible loss of the unknown.

Some images from around the new plantings...



American Bellflower, Campanulastrum americanum, tall, short, welcome.



Bottle Brush Grass, Elymus hystrix, great medium height grass in the shade.



Royal Catchfly, Silene regia, a red like the Scarlet Tanager, loved by humming birds, although not native to Minnesota, it does okay, if a little sickly in the leaf by flowering time.



We've had countless monarchs this year. They love the new plantings, as do swallowtails and more.




For about a month she rebuilt the web daily outside our kitchen window. Spider watching and dish washing -it's all the rage.



Side Oats Grama, Bouteloua curtipendula, or as I like to call it: Grandma.



The warm season grasses, unlike those of the lawn, have colorful flowers.




Saturday, June 9, 2018

Sedges Have Edges, Rushes Are Round, Grasses have Nodes...




It all started with a blizzard that pushed us right into excessive heat of summer before May was out. We hadn't had more than a few hours rain over the month, so little that, with the heat, high sun, and drying wind, even succulents were bowing to the ground.



By Memorial Day, rising heat and moisture became the cauldron from which storms could manifest. 



Our woods and garden had accumulated three inches of rain by Tuesday. Another five eighths came later that day. This broke the drought, for now, and not everywhere, but in our woods. It also spared two climbing roses that we transplanted along with an arbor from a rapidly shading garden, on one of the hottest days, when rain looked immanent, but wasn't.



Was it the rain, or the freshly loosened soil under the trellis, that brought my first turtle sighting to our clearing in the woods? By early morning, this medium-large sized snapping turtle, Chelydra serpentina, made its way up the slope from one of many watery sites and began depositing her eggs directly beneath the newly moved rose trellis. By mid morning she was gone and around her clutch, Betsy installed a fence to keep out likely predation by raccoons (just steps away is a perma-puddle with not-so-little raccoon "hand" prints scrawled across the bottom). In fifty or one hundred and twenty five days the little ones may emerge from the nest.



The rain also gave a much needed boost to the garlic on both farms. Already stressed by the latest of winters, drought had begun to take its toll. The garlic is about the size it would normally be in early May, although the date is early June. The rain also gave boost to the mass of thistle, grass, and lambsquarters in this new plot, all weeded this past Sunday with one more weeding likely before harvest.



In the other plot, the weed profile is completely different: smartweed, bindweed, and purslane. The garlic is generally larger here, although still less vigorous than should be at this time, with many lost cloves of artichoke, turban, asiatic, and creole. In either of these two plots I picked up my first embedded tick, the wood type, as I wore shorts for the chore, something I have not done before. For all my traipsing around in the woods and elsewhere, I have yet, until this moment, to have a tick embed itself. In fact one would not anticipate that the garlic plots are where I would pick up ticks given how much time I spend in the woods.



In the year old savanna gardens a cool season grass has come up to fill the blanks readily and, although attractive, my suspicion is that it was unlikely to have been seeded with the shortgrass or savanna seed mixes broadcast in these sites a year and half ago. Nothing triggers plant weariness or all out blindness more than grass identification, but grass identification is often needed and difficult.



A last minute reprieve was handed out by the folks at Minnesota Wildflowers, a site dedicated to visual identification of native Minnesotan plants and those we find among them. In this instance, my picture post on their FB page lead to an ID a few days later, prompting me to immediately begin pulling. I hazarded the guess that it came with the poor quality straw purchased from a local farm supply. It was only in those areas where I had spread the straw for erosion control that the new weed, Cheatgrass, Bromus tectorum, as well as common oats had sprouted.

It's only then, after a positive ID, that traits of a weedy species appear to express themselves clearly. Each day since, I continue to find more inflorescence hidden among the other forbs and grasses. Like any impressive weed, this grass exhibits the ability to grow from the base of other plants and set seed at heights of only an inch. At the same time, this winter annual (cool season) grass can take advantage of rising CO2, thereby increasing its biomass, indigestibility, and fire threat. Not long after, I begin to see other grasses that appear similar to Cheatgrass, but maybe taller or with smaller inflorescence, maybe smoother stems or less blue coloration in the leaves and stem. What then?



Can you tell the difference between these two grasses? Side by side, you may notice differences, but in the field grasses can blur together.



Spot the different grasses in there? From this picture, it looks to be all forbs, but it is likely 40 to 50% grasses. As the shortgrass mix I scattered here two winters back consisted of predominantly Side-oats Grama, Bouteloua curtipendula, and Little Bluestem, Schyzachyrium scoparium, a sensible guess would be that some of these grasses are present. Little bluestem is fairly easy to identify as a warm season, low growing, bluish bunch grass -not the predominant grass here.



Upon closer inspection, the grasses become more visible. Non-weed, perennial grasses tend to grow slower than annual weed grasses, but also slower than the annual forbs such as the first-year predominant black-eyed susan. In this second growth season, the grasses are making themselves known and the black-eyed susan are spread more evenly and less thickly. The site also has plants that I have cell-tray seeded and planted last summer and fall as well as more mature plants transplanted from other locations.



This grass, blooming now, is scattered through the site. It may be Fowl Manna Grass, Glyceria striata, but then again, I'm not sure. To become an expert in grass identification, one must make solid observations. The easy part is cool season, warm season or bunch or spreading, but in an ascending order of difficulty we have dull or shiny, pubescent parts or not, ligules formed this way or that, leaves folded or flat, sheaths fused or unfused, and on. It helps to know general things about a species, such as preferred habitat or weed status, but that only opens the door to more complex examination.



It is clear that the creatures appreciate these clearings repopulated with food and shelter. The milkweed planted two summers ago have begun to establish solidly among the grasses, monarda, goldenrod, asters, and much more.



These sites are a favorite of large and small dragonflies, monarchs, toads, and moths such as this Xanthotype species.



What's this? A new concept in contemporary landscape architecture? No, its a sheet of thick plastic designed to combat what was once grass, but now is one hundred percent creeping charlie, Glechoma hederacea.



It only took three years for it to go from sporadic lawn weed to total ground cover and the reason is largely due our garden choices. Putting vegetables in the lawn area, where we had our only sun, or making a hedgerow along the driveway edge created shade that charlie took advantage of. The wet weather over the last two years and our heavy clay soil worked well with our yard plans to bring us this new idea in lawns.

Why is it that a monoculture of grass is more desirable than a monoculture of charlie? After all, charlie feeds the bees and smells great when crushed (insert someone offering its medicinal value here). Is it a texture thing, a cultural, or visual thing? Lawn grasses, like charlie, are weeds around the world, but maybe we don't see grasses (remember grass blindness...). For us, a creeping charlie lawn comes down to at least three negatives: this "lawn" will always be the spring of more charlie invasions in the woods, the visual texture is off putting, and it's a pain to have to weed this out of every shady nook in the yard and garden.



Charlie hides out in the shady base of perennials, between stones, under dense shrubs, and just about anywhere there is shade and moisture. Its stolons spread in every direction, with a preference to run toward shade. At our place that means downhill, toward the woods, where it is becoming an increasingly problematic ground cover. Its seeds roll downhill in rainstorms and get stuck in clay-filled shoe treads, but worse is how its bits and pieces follow raked leaves onto slopes.

I have my eyes on several infestations, one of which looks not all that different from the lawn, but under the canopy of trees on a north facing woodland slope. In fact, charlie is giving garlic mustard that grows there a hard time, but the garlic mustard is much easier for me to eradicate, with or without its help.

After the plastic comes up this summer, the idea is to till the soil, add compost, and place thick sod in its place. It's a good idea if we do not grow vegetables here any longer. Maybe we should grow vegetables here, but add sand and brick between the raised beds? No matter what we do, charlie is instigating a lot more work and we've already plenty of that.