Category Archives: Plant Communities

Latitude and Energy: A Beginning Point

45º!  In my previous post I suggest, for reasons of solar gain and intensity, that we gardeners might have better luck choosing plants for our gardens if we chose them from our own latitude, north and south.  The intensity of the sun’s radiation varies with latitude, decreasing as we move away from the equator toward the poles.  Like all horticultural suggestions you should take this with a grain of salt…er, soil.  Follow that line around the Earth from Portland and you can run into a lot of difficulty.  Spin a globe and take a look.  Following the 45 parallel east takes us along the Columbia Gorge, across the Blue Mountains, Hell’s Canyon, the resort town of McCall, Idaho, elevation one mile, the Frank Church River of No Return Wilderness and more of the Rockies, on across the northern Plains, through South Dakota, Minnesota, Michigan, our ‘frozen heartland’ and east through New York and just outside Portland, Maine.  These are highly varied landscapes with conditions almost always colder, different rain patterns, more extreme weather conditions than ours with corresponding plant communities.  In Europe 45º passes through northern Provence, with weather strongly influenced by the adjacent Mediterranean Sea and the massive Sahara Desert that lies beyond, the Piedmont region of Italy, Croatia, the Black Sea, the Steppe country including Uzbekistan, into northern mountainous China and southern Mongolia and finally, the Japanese island of Hokkaido, its capital, Sapporo, a couple degrees south, with its remarkable annual ice festival. 

The list of landmarks found along the southern 45th is very short, as the vast majority of its length is defined by open ocean.  Still it crosses New Zealand’s South Island, only again making landfall in the south of Argentina where it narrows down toward the continent’s southern tip and the Chonos Archipelago of small Chilean islands comprised of submerged mountain tops.  On the later the landscape is dominated by compact cushion plants.  These few places have strong maritime influences and are much effected by the unimpeded weather sweeping off of Antarctica.  Much of this sounds limited and extreme when I think of plants adapted for our region. Continue reading

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Agave montana: Monte’s Flowering Attempt…and What’s Behind It

It’s October in Portland and my Agave montana is in the process of flowering…I know, we’re heading toward winter, with its rain and average low down into the mid-30’s with potentially sudden damaging temperature swings from mid-November into March dropping below freezing to the low twenties, with extremes some years, generally limited to the upper teens, though historically, some areas have dropped into the single digits, those Arctic blasts from the interior….Winter temps here can be extremely unsupportive of Agave’s from ‘low desert’ and tropical regions.  Combined with these cool/cold temperatures are our seasonal reduction in daylight hours and its intensity (day length and angle of incidence varies much more widely here at 45º north) and the rain, ranging from 2.5″ to 6″+ each month here Nov.- Mar., resulting in a ‘trifecta’ of negative factors which can compromise an Agave, even when in its long rosette producing stage.  Any Agave here requires thoughtful siting with special consideration for drainage, exposure and aspect.  For an Agave, conditions common to the maritime Pacific Northwest are generally marginal, yet I am far from alone in my attempts to grow them here.  Previously, in April of 2016 I had an Agave x ‘Sharkskin’ flower, a process that spanned the summer months, taking 7 until mid-October to produce ripe seed.  I was initially a little pessimistic this time about A. montana’s prospects.  Why, I wonder, if plants are driven to reproduce themselves would this one be starting the process now? Continue reading

Agave colorata and its Blooming Attempt in ’18

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Agave colorata before flowering initiation, growing nearly horizontal, with a broadly cupped lower leaf holding water. From the Irish’s book, “Agaves, Yuccas and Related Plants”, “The leaves are 5-7″ wide and 10″-23” long [mine were all at the small end of this range] They are ovate ending in a sharp tip….The leaves are a glaucous blue-gray and quite rough to the touch. The margin is fanciful with strong undulations and large prominent teats of various sizes and shapes. A very strong bud imprint marks the leaves, which usually are crossbanded, often with a pink cast [not mine], and end in a brown spine 1-2 in. long.

This is one of the first Agaves I ever grew. Pictures on line of its rosette first caught my
interest, their leaf color, substance and sculptural qualities, the margins of its broad, thick leaves, with their rhythmic rounded ripples, each tipped with a prominent ‘teat’ and spine. This is not a large plant, typically growing 23″- 47″ in diameter and my plan was always to keep it in a pot as it is from coastal areas of the Mexican state of Sonora, found sporadically in a narrow ‘band’ south into Sinaloa.  Agave colorata is very rare and uncommon in nature and growing on steep slopes of the volcanic mountains in the coastal region in Sinaloan thornscrub. It often emerges from apparently solid rock cliffs sometimes clinging high above the water below.

Growing in Sonora and at Home

It is poorly adapted to our wet winter conditions though it is reputedly hardy into USDA zn 8, or as low as 10ºF.  Its natural northern limit is thought not due to cold, but by excessive aridity in the northern parts of Sonora.  I didn’t test it, leaving it outside under the porch roof, bringing it in when forecasts called for below 20ºF, as any plant is more susceptible to cold with its root zone subject to freezing. With perfect drainage and overhead protection, you might be able to get away with this in the ground, but the combination of significant wet with our cold is likely too much…still if someone wanted to try….At best I suspect this one would still suffer from fungal leaf diseases, disfiguring the foliage.

This is usually solitary, but it can be found occasionally in small clumps/colonies up to nearly 10′ across, pushing up against each other on their slowly growing and short ‘trunks’ to 4′ high.  My plant produced just a few pups over the first third of its life.

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I wanted to include a climate map of Mexico. This one utilizes the classic Koppen system designating the various climates based on temperature and precipitation and their seasonal patterns. Here it has been modified by Mexican climatologists to better reflect Mexico’s complicated geography…even so, because of the abrupt changes in elevation, and land forms, different climatic conditions can occur in close proximity to one another. Mountains can create wetter and drier areas that on a map of this scale are lost.

Sonora has three distinct geographic areas all running along a ‘line’ from the northwest toward the southeast, the Gulf of California and its associated coastal landscape paralleling the Sierra Madre Occidental, sandwiching plains and rolling hills in the middle.  The coast and plains/rolling hills are arid to semi-arid, desert and grasslands, while only the higher elevation of the easterly mountains receive enough rain to support more diverse and woody plant communities, scrub and Pine-Oak forests.

This map comes from the Arizona Sonoran Desert Museum. The link takes you to one of their pages which discusses the natural history of the desert, thornscrub and tropical deciduous forest of Sonora.

This region also varies north to south, the climate drying as you go north into the Sonoran Desert.  Moving south on down into Sinaloa, and further, is the some what wetter ‘dry deciduous forest’ biome with an array of woody leugumes, including several Acacia.  Agave colorata resides in the transition zone in between, in the portion of  ‘thornscrub’ near the Sonoran/Sinaloan border.  North and south the Thornscrub itself changes in composition.  The Sinaloan Thornscrub serves as a transition zone between the desert and the slightly wetter, taller growing, Tropical Deciduous Forest that continues the south.  All along this band running north on into Arizona’s Sonoran Desert are various columnar cactus a food source for Mexico’s migrating nectarivorous bat species.  It is a unique flora community, containing species from bordering floral regions and other species unique or endemic to this transition zone itself.  The area continues to be under threat, primarily by cattle ranching that moved into the region in the ’70’s and ’90’s bringing with it clearing and the introduction of non-native and invasive Bufflegrass, Pennisetum ciliare, also known under its syn. Cenchrus ciliaris, for pasture.  Bufflegrass is also a serious problem north into Arizona.  In Sonora many of the cleared woody species have since begun moving back in, while the smaller, more sensitive species have not.  Climate change promises to further squeeze it. (The World Wildlife Fund maintains a website with good descriptions of many eco-regions I sometimes find it very helpful when trying to understand the conditions of a plant I’m less familiar with.)

When growing plants like this, one should keep in mind the concept of heat zones.  The American Horticultural Society has created a map of the US delineating its ‘heat zones’.  It is based on the average number of days an area experiences temperatures over 86ºF.  At that temperature most plants begin to shut down their metabolic processes…they slow their growth.  Check out the AHS map (AHS US Heat Zones pdf.) and keep in mind that we are warming up!  The AHS map has us, Portland, OR, in zone 4, meaning we experience 14-30 days with highs over 86ºF each year.  Last summer, ’18, we actually had a record 31 days over 90ºF!  Now consider that the coastal/plains region of Sonora likely experiences between 180-210 such days!  Agave colorata may not need this, but it is certainly adapted to such a level of heat stress.  Something to think about, especially when you consider that we receive the bulk of our rain over the winter when our daily highs and lows average for Nov. 40º-53º, Dec. 35º-46º, Jan. 36º-47º, Feb. 36º-51º and Mar. 40º-57º…keeping in mind that we could freeze on most any of those dates.  The Sonoran Desert receives its minimal rainfall in a summer/monsoonal pattern….This is why bringing such ‘low desert’ plants to the Pacific Northwest can add another degree or two of difficulty to your success!

 

Growing this in a pot made perfect sense to me, but every decision carries consequences, not all of which I anticipated. Most Agave don’t form a ‘trunk’ growing its leaves, in a tight spiral, crowded along a very abbreviated stem, which adds little to its length to separate each consecutive leaf., but Agave colorata adds a little ‘extra’ slightly separating its leaves, resulting in a weak and kind of puny stem. If you’ve ever shuffled pots containing Agave more than a few years old, you understand that their crown, their substantial top growth, is relatively heavy, A. colorata is no exception, in fact their leaves each seem more substantial than leaves on many other similarly sized Agave. This results in a plant that as it grows begins to lean over, eventually, laying flat across the ground. As a Monocot the stems of Agave don’t caliper up over the years as does wood. These have no cambial meristem which would add secondary growth, and diameter, to the stem and as I said, with its relatively massive and heavy crown, it leans.  This is the same characteristic that gives their small colonies their height.

 

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A Course Correction: The Wild and the Human, On Repairing the Relationship Between Politics, Economics and the Environment

“We are the odd ones, with bright eyes, that see the wonder of a bountiful world.  We don’t look through rose colored glasses…we’ve only removed the veil that breaks and blinds….Now, to cut the strings that tie us to the lie. ”  Lance Wright, Jan. 2019

Echinops ritro in front of a Miscanthus gracillimus several years ago at Holladay Park. A series of perennial beds were created with help from a notable local designer. For a variety of reasons related to budget, staffing and vandalism, the beds declined.  Beauty, that necessary elixir, truly abounds, but we must be cognizant of the forms in which we accept it and be committed to what it requires to flourish.

Gardeners are my people…well, actually, so are botanists, horticulturists, entomologists, ecologists, the weekend outdoor adventurers who in regular moments of awe, pause to take in the daily wonder of the world…anyone, really, who works with or has become enamored with the living natural world (and I’m going to include geologists too, at least those not taking their livelihood from resource extraction).  I have a theory, that as our modern world becomes increasingly urbanized, and transformed by our use to that which supports urban living, more of us are becoming consciously aware of what we are losing, of the natural world that has been sacrificed, developed, along the way…and in ways, large and small, many, but still far too few of us, are choosing to make our lives reflect this understanding. We question the ‘stuff’ we have crowded our lives with, that ‘stuff’ we’ve spent our lives to procure while following the dream we’ve all been sold on.  Many of us garden on whatever we have available to us whether it’s a quarter acre, a Juliet balcony or a kitchen counter space.  We plant gardens for food or to support pollinators, to have something green and growing in our homes, we grow small succulents for their simple beauty, flowers for the vase or plants that provide cover and fruit for songbirds, there are many reasons…and we do this for the pleasure that it gives us, for the satisfaction that we are doing something to heal an increasingly ‘broken’ world.  Yet the world continues to spiral down into more ugly chaos, in spite of our increasing awareness…it is not enough.  I find myself drawn even more into the wonder and beauty of a single plant, the ‘miracle’ of life and the amazing complexity, the inter-relatedness of living communities…because, in spite of how our society views this planet and the countless organisms it routinely dismisses as secondary, and unnecessary or of little commercial value…life is in fact the center of meaning and value. Continue reading

On Our Expulsion From the Garden: How Our Ideas of the Garden Shape What We Do

There are those who argue that life is short and violent, that we have nothing to look forward to other than our deaths…so we might as well grab for whatever we can now!….that is the path of the nihilist and the greedy, it serves as an excuse, a rationale for their choices, following an ethic of ‘why the hell not!’  This is consistent with the ‘beliefs’ of those who feel the weak get what they deserve, that anything that opposes their idea of dominance, is weakness and failure and they pursue it with the righteousness of a ‘true believer’.  “Only the strong survive”.  If our gardens can teach us anything it is instead that, ‘He/She who has the graciousness to take only what they need and gives back whatever they are able to, live on through the love and lives of those and that which they’ve nurtured, helped, befriended and mentored along the way and in this way have helped build a richer, more complex and diverse world.’  Our true legacy will be best expressed in the richness and health of the world we leave behind, of those that we’ve loved and taught.  As competitive as the world is, it is this positive, cooperative, supportive aspect of life that makes it all possible.  While the world is divided into heterotrophs and autotrophs, those that must consume to live and those able to grow and metabolize that which they need from the world around them, it requires them both, working in a balance to sustain them all.  We humans, ultimately, cannot be any different if the world is to continue on. Continue reading

Winter 0f ’18 -’19: Cloudy, Mild With a Chance of….On Weather, Zones & Plants

It’s 41ºF at 5:30am on Mar. 12 as I begin to write this.  We appear to have come out of the longest sustained ‘cold’ period of the winter of ’18-’19 which began on February 4 and continued through Mar. 11, a period of 36 days.  Over those days we had freezing minimum temps at PDX, the official NOAA reporting station for the Portland area, on 26 of them.  On two of those days, Feb. 6 and 7, PDX recorded the winter’s lowest temp, 23ºF, making it a zn 9a winter, mild for us historically and especially so for the temperate US as a whole, much of which was experiencing its own much colder temps.  It’s mid-March and our high temps have climbed well above what they were and our forecasts call for milder, more ‘normal’ highs and lows now locally.  It looks likely that not only are we going to be on the ‘warm side’ of normal, but that our lows have shifted into a pattern well out of the freezing range.  (State ODF meteorologist, Pete Parsons, calls for a pattern of slightly warmer and drier weather than normal over March, April and May with the highest chance of this during May.) 

While weather consists of moments, recorded data points, we attempt to make sense of it in its patterns over time…our experience of it.  In this we are much like our plants.  Plants too have their ‘expectations’ of the weather and those conditions that take them outside of them, outside their familiar patterns, the relatively quick changes and perturbations, as well as the longer sustained patterns, and extremes, are ‘noticed’ and make a difference.  How does this winter compare? Continue reading

Death and Life in the Garden: Learning in the Garden Classroom

As gardeners our hands are ‘bloodied’ with the chlorophyll of plants…while it may not stain us as ‘murderers’, we are never the less complicit in their deaths…as much as we are necessary for their lives.  Without us, as a group, these garden plants would never would have been propagated and, if not for our ‘selfish’ acts in the garden, choosing, designing and displaying them, many would be passing into obscurity, most of us knowing nothing of them or of their loss, their passages into decline and extinction, even more quiet, unnoticed, as too many already do today.  While we may acquire and attempt to grow them with the ‘best’ of intention, eventually, they will all die, ill fit or not, suddenly or after many years in our gardens, as a result of our ignorance, impatience, simple curiosity, our desire for something ‘different’, or even in spite of our best informed efforts.  Death comes to all things and our gardens are no exception.  Our gardens art artificial after all, creations of our making and they do not comprise a viable population that will out live us, reproducing in place, making the adjustments that they must over time to survive.  To do this would take an unprecedented amount of effort and coordination on our part and that of our neighbors.  The setting of our gardens are unique to us and their purposes are much narrowed and more intentional than are the places their progenitors come from, the ‘gardens’ of their origination.  For many of these plants our relationship with them might best be thought of as student to teacher as nature sacrifices itself in an attempt to teach us of what is being lost, ever since we stepped out of the loop that once put us in daily direct contact with nature and came to embrace this modern world and its expectations of consumption, ‘ease’ and never ceasing growth…so it is not ‘murder’, it is life, an attempt to return and reclaim.  There is purpose to be found in our gardens, well beyond surface amusement and distraction in what is too often becoming an ever uglier world, or for some of us our need to impress in a game of one-upmanship.  Nature demands more of us, that we accept our role as student and become careful observers, willing acolytes…maybe even crusaders….Too much? no, I don’t think so. Continue reading

Our Gardens as Teachers

 

Of all the things our gardens do for us, arguably the most important is their role as our teachers, even in winter when a temperate garden ‘rests’, its surface crust or top few feet, frozen, maybe sheltered beneath the cover of snow, or, as ours so often are, simply too cold for active plant growth, the soil wet, the rain too heavy to percolate fast enough down through its layers, without the active aid of either the direct heating of the sun or its effect on plants, through evapotranspiration, pumping water back into the air as the plants grow.  Gardens teach patience.  They encourage us to become more careful observers…to think and plan, to anticipate and prepare, to understand that there is more going on here than we can readily see…and they teach us about faith and trust in the natural world, that there is always more going on than we can see. Continue reading

A Closer Look at Jimi’s Beautiful Obsession, A Review of Chosen Plants From his Presentation, Part 1

It would seem that gardeners are a difficult lot!  For those of us intent on gardening with ornamental plants we are continuously drawn to the exotic and novel, sated less and less by the plants in yesterdays’ garden…at least until those have had suitable time to have fallen out of fashion and are rediscovered. For most of us it is the plants we’ve never grown, or even seen before, that draw us.  This is as true when we ourselves are novices as it is many years later.  Sure, we all have more than a few long term relationships with particular plants, but we seem forever subject to the seductive calls of the unknown (to us)!  For many of us this is at no time more true than when nurserymen, on the ‘cutting edge’, and plant explorers come to town, especially if they come bearing pretty pictures…Even mores so when paired with the opportunity to acquire them.  Instant gratification.  It is a conspiracy you know. Continue reading

The Lower Deschutes River: the Incursion of Invasive Plants and our Failure to Responsibly Maintain Native Plant Communities

This picture should give anyone more than enough reason to visit here, the Deschutes sliding out its mouth into the Columbia with the Washington side of the Gorge in the distance, the low angled early evening sun illuminating everything sharply.

 

[As I go over this post yet again, July 21, the 80,000 acre Substation Fire is still burning across canyon and wheat country here.  Included in the blaze are the 20 miles of the Lower Deschutes canyon down to the campground at the confluence with the Columbia.  Much of this burned down to within 2′ or 3′ of the riverbank including the historic Harris Ranch buildings.  So, when you look at all of these pictures, with the exceptions of where the fire hopped and skipped, everything is charred.  The Oregon Wildlife Federation, formed in the 1980’s to purchase and protect this portion of the canyon, has stepped up with $100,000 to help the area recover.  It will take considerably more especially if there is any intention of making headway regarding the spreading invasives problem.]

[Now, another 2 weeks later more massive fires continue to burn across the dried up West that has just experienced another record breaking month of heat, while the president goes on ‘bleating’ and blaming it on our ‘bad’ environmental laws and all of the water we’re diverting into the ocean!  ‘F’ing! moron!]

The last time we came here was eight years ago in December.  My memory of then is much like the experience on this evening…only it was clear and cold.  The light was similar except that then the low angled sun was due to winter, with that season’s urgency, not a late Spring evening like this outing.  This time it is warm, camp is comfortable and nearby and the greens are still gathered around the river and the still moist draws and seeps.  On that day we’d gone to Hood River for my birthday, to get out of town and there was a break in the weather so we drove here to these trails at the mouth of the Deschutes, hiked along the river, returning on the upper springs trail.  Winter or summer, green only sticks around a little longer than we do, before it retreats…life is shier here, tough, but shy.  The starkness of this landscape should be read as a warning to visitors, this is no easy Eden.  Life is earned here or at least requires a strength, patience and frugality that many don’t have.  This is much the same for people as it is for wildlife and plants.   Them that don’t, can’t.  That’s why it may be surprising to some that such a place has a problem with exotic invaders.  What could possibly look on places such as this as ‘favored’?  Well, Central Asia, especially its Steppe, with its continental, cold and dry climate containing many species that see such a place as this as home, or even better, without the competitors they faced back there.  The temperature can swing widely here on any given day while the seasonal extremes can vary as much as 125ºF from high to low.  Relatively few plants can thrive in this.  The dry summers with their very limited and sporadic thunder showers, combined with the ‘wet’ winters, total only 10″-12″ or so of precipitation, plus or minus, is another major limiting factor.  Of course, near the river, the moisture problem is moderated  and a broader range of invasives can find a ‘foothold’.  We, as a people, have ‘brought’ these weeds here with us in our travels, often as a result of our commerce.  Those that have made it here are spreading.  Too many prosper. Continue reading