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Where the wild things are, go I

30 May

Last week was a string of days within this:

Malheur NW Refuge and Steens Mnt.

We enter solitude, in which also we lose loneliness…

True solitude is found in the wild places, where one is without human obligation.

One’s inner voices become audible. One feels the attraction of one’s most intimate sources.

In consequence, one responds more clearly to other lives. The more coherent one becomes within oneself as a creature, the more fully one enters into the communion of all creatures.
– Wendell Berry

The ultimate was watching a pair of swans with four cygnets. Watching for hours the intimacy of their body language with each other, their communication and connections so basic and honest simplicity, putting all of ours at shame and bumbling inadequacy. The poetics of space and place through the eyes of six swans was an experience I won’t forget. And it makes all our human drama seem so ignorant and trivial.

I belong where the wild things are.

Trumpeter swans and cygnets

White-faced ibis and cinnamon teal on marshes on the Refuge.

Choices

23 May

It was my free choice to release all the stuff and trappings in life and live simply where I want. Poor, yet very happy in the natural world. I wouldn’t trade it for anything else.

 

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Sagebrush Galls: Medusa!

16 May

“How galling!! The audacity of this insect making a home in me!”

True; no matter how one organism looks at it, it’s annoying. The word ‘gall’ originates from Middle English (~ 900 A.D) and refers to bile, the bitter fluid from the gall bladder. The figurative word ‘galling’ refers to irritating, offensive, audacity and very annoying behavior.  But how did an abnormal plant growth acquire the same name, gall?

We may never know.

As a child roaming the woods and wild fields, I would often collect tree and shrub leaves and twigs that had protruding bumps in a variety of shapes.  I wondered what these odd shapes were, but it never occurred to me that they might be injurious to the plant, or even malicious at all. Nor did I know then how they were formed.

One day while wandering in the field I found a particularly large growth on the stem of a shrub. Pulling out my magic little ‘looking glass’ (pocket magnifier), I watched half a dozen little translucent bugs crawl out of the ball-shaped growth. In a short time, these bugs acquired color and their wings unfolded away from their bodies. I wondered if the abnormal-looking ball of green was a home for these bugs, and only much later did I learn they were called ‘galls’. And from then on, anytime a person uses the word ‘gall’ or ‘galling’, all I can think of are these appropriated plant cells that serve as a home for small insects.

Five decades later and I’m still fascinated by galls!

Here in the high desert of the Great Basin, galls are common on sagebrush, the most dominant plant. What surprises me is the morphological variety of these galls: the colors, shapes and sizes. So, like the child I was (and probably still am), I have been collecting samples to take back with me, as well as photographing them.

What are galls, anyway?

Galls are an abnormal plant growth induced by various parasitic organisms (1), usually insects. These latter galls will be the focus of a series of posts here as I find examples.

Galls serve as ‘incubators’ for developing insects where they gain nutrition and protection from environmental conditions and predators. Some galls are colorful and easily distinguished from the other plant material. Some are wooly, some round and colorful like tiny plums, some are lobed, and others have spiky protuberances.

Gall-inducing insects are usually species-specific and sometimes tissue-specific on the plants they parasitize. Galls can be found on leaves, stems, shoots, flowers and roots. Combined with gall morphology, these traits will often help to identify which insect is associated with them. However, identifying the insects inside will be the confirmation.

These insects manipulate and exploit the chemistry and physiology of plant tissue to their own benefit and development. Accordingly, galls act as physiological sinks for mobilized plant resources, mostly as nutrition for larvae. Fungi sometimes grow on the interior of the gall surface on which the larvae feed.

Like little houses, galls physically serve as protection from the sun, wind, rain and snow. In fact, because the gall-forming insects control gall formation so well, galls are commonly referred to as their extended phenotype. However, several predatory insects have also adapted to this system by inserting their own larvae inside galls. Then a battle for who eats whom ensues until maturation of one or both species. It’s not uncommon to have more than one species of insect emerge from a gall, but only one of those species induces galls.

Protection is one explanation for the high levels of compounds, such as phenolics and tanins, found in many galls. This is considered a defensive gall trait, protecting the gall against natural enemies outside. Thus, in addition to serving as a nutrition sink and physical protection, some galls have a natural chemical defense.

Sagebrush gall midges

Like any plant, it’s an insect-eat-leaf world out there for sagebrush. Of the 237 species of insects that are associates of sagebrush, 42 are gall-forming insects. Of those, the most predominant are Cecidomiidae, or gall midges. They are a small family of tiny flies that are associated with gall induction.

The most abundant gall midges found on sagebrush are of the Rhopalomyia genus. Although there are 32 species, not all may be present in the same location and area. A recent study suggests that land use or local abiotic conditions may greatly influence the diversity of gall midges.

The adult midges lay eggs in the sagebrush stem tissue. The eggs hatch and the larva secrete saliva into the plant. Compounds in the saliva alter the growth of the injured plant cells and the tissue produces a swelling, or gall, around the young insects. However, the size, shape and color of the developing gall are typically specific to the gall midge species. On the other hand, one species unusually induces a wide range of gall morphologies.

Medusa Galls

During a recent camping trip on Steens Mountain in SE Oregon (and bordering the Refuge), I found many specimens of Medusa galls (Rhopalomyia medusa) on Big Sagebrush (Artemesia tridentate). As seen in the photograph, these galls are composed of numerous leaf-like structures. Looking at the long miniature leafy structures, it’s easy to see how this gall was called “Medusa”.

Medusa Gall on Big sagebrush

The galls develop in October and rest during the winter. They reach full size in the following spring and adult midge flies emerge in April or May. When I was there, May 9-11, the galls were intact with no sign of emergent flies. Considering the elevation (7,300 feet) where I was hiking, patches of snow were common and the climate was barely spring-like.

Authors of a study (2) sampled arthropod diversity on sagebrush in two ecosystems, one surrounded by dryland agriculture and the other area protected from agriculture and significant human use. Their data suggests that diversity of gall midges is highly variable with the dynamics of arthropod-sagebrush interactions and the sagebrush ecosystem. Interestingly, R. medusa was one of a few species that served as an indicator species in low human impact sagebrush habitats. A good description of where I found the many specimens on Steens Mnt.

So, do these galls negatively affect the sagebrush? We will examine that question in a later post!

1. Some bacteria species can also cause galls. This was my first introduction to galls in undergraduate university. Crown gall (Rhizobium radiobacter, formerly known as Agrobacterium tumefaciens) is the textbook and lab example used in plant pathology and lab classes. It is also a common tool to teach Koch’s Postulates. Soil bacterium inserts a small segment of DNA (T-DNA) from a plasmid and into the plant cell. This DNA encodes for genes that produce a plant hormone, auxin (indole-3-acetic acid), via a special pathway that is not used in most plants. Thus the plant has no molecular means of regulating the production of the exocrine hormone. The T-DNA also signals extra production of a group of plant hormones called cytokines, which are involved in cell division. These hormones are responsible for the tumor-like growth of plant tissue and form the galls.

2. Sanford, M.P., Huntly, N.J. 2010. Seasonal patterns of arthropod diversity and abundance on Big sagebrush, Artemisia tridentata.  Western North American Naturalist, 70(1): 67-76.

Northern Great Basin, Round Two

5 Apr

Example of igneous rock from volcanic deposits of ash, later terraformed by rifting, faulting and moving water.

No matter where I go in this open country, the high desert of the northern Great Basin finds me smiling inside and out.

My first immersion in the high desert here in southeast Oregon was in 2010 when I spent two weeks living off the back of a 350cc motorcycle. It’s springy high suspension and knobby tires allowed me to travel in the backcountry. Most nights were spent in a small tent and warm sleeping bag, under a dark sky bejeweled with bright stars that couldn’t be found where I was living in Texas during that time in my life. From dust to snow and freezing rain to hot dry sunshine; from owls screeching overhead to a silence that roared in your head, it was all memorable.

I didn’t want to leave.

The transition from the Cascade mountains with giant scaly pine trees to the dry deserts was transforming. Standing on an outcrop, a memorable scene stretched below. Black volcanic seams and outcrops meandered through a gray-green carpet dominated with sagebrush. Ribbons of blue streams whose edges bristled with willows tickled that instinctive draw towards water. Occasional water-filled basins reflected the white clouds overhead, while dry playas were ground-clouds of dried white salt or lime.

Every time I come here I am reminded of similarities with my beloved Big Bend desert in southwest Texas. The high desert here shares geological and climatic features with the northern Chihuahuan desert, albeit colder in winter and less hot in summer. Topographical features here, typical of Basin and Range*, can be suddenly dramatic or gentle. Here are also the ‘big open skies’ that endear Big Bend to many people. Magnificent sunrises and sunsets are never boring here. And the clouds, from daily cotton balls to dramatic forms imparted by storms are continual award-winning players on the atmospheric stage.

Yet this is a kinder and gentler Big Bend; few thorny plants to grab and bite you, an astringent and intoxicating scent of sagebrush, and more recent volcanism. The most compelling feature for me is its presence of water. This is a land where land and water meet. It is a juxtaposition of water and dry climate and land. Consequently, the diversity and population numbers of wildlife outnumbers those found in Big Bend. Life here, and its interaction within the variety of ecosystems, is never boring. This overlap of water and land can’t be found in such intensity and variety in Big Bend.

Marshes fed by snow melt and crucial for migrant and summer nesting birds on the Pacific Flyway. MNWR.

Last summer was my introduction to Malheur National Wildlife Refuge and the surrounding area. This spring and summer will be like jumping in with both feet and getting my hands and feet dirty. Thus far, my first week has been quite rewarding. And I promise to post more about this region during months to come.

* For a primer on the geography of the northern Great Basin, see an earlier post from last summer (2014). Another post describes more local geography of the Harney Basin.

High Desert & Great Basin. Part 2

24 Aug

“Cataclysmic transformations such as moving continents, lava inundations, freezing Ice Ages, and apocalyptic floods exterminated entire plant and animal communities while successive new life forms adapted. Relative to these expansive epochs, human life spans seem but mere seconds in duration. This myopic snapshot of our current familiar environment with its modern species can foster an inaccurate perception of unchanging surroundings. But the fossil records tell us otherwise.” – Alan St. John, author of Oregon’s Dry Side.

Climate change is not a stranger to the Pacific Northwest. With two mountain ranges that run north and south, modern residents and visitors can experience the coastal fog or cool and temperate summers and winters in Oregon’s Willamette River valley between the Coastal and Cascade mountain ranges. On the east side of the higher peaks of the Cascades, and in the rainshadow of these same mountains, lies central and eastern Oregon. Here, springtime is later, summers more hot and dry, and winters cold and snowy. Yet a common denominator throughout the state is water, just in varying volumes and persistence. Water is not a stranger to even the most arid regions of modern Oregon.

Not only did Oregon’s terrain change and shift numerous times, so did the climate. Fossils from eastern and central Oregon, especially from the John Day River area, reveal the climatic conditions and the flora and fauna that lived in the area beginning 55 million years ago (mya). After a long period (~10 my) following global decimation by a planet-wide catastrophe in the Paleocene , life began to repopulate the entire continent. The Pacific Northwest became a lush subtropical region dominated by forests. Small mammals that survived in small pockets during the catastrophe began diversifying into a multitude of forms.

Conditions shifted again, possibly due to another global catastrophe,  some 34 mya to a cooler and drier temperate climate. Grasslands replaced subtropical forests and animals more suited to grazing dominated, as did their predators. This cooling trend continued on into the Pleistocene and culminated in the Ice Age.

Climate in the Pacific Northwest shifted again 10-12 thousand years ago back to more temperate conditions. The ecosystems we see now are the results of this shift. This long and active changing geological and climatic history has left its marks on the land and the life that lives on it.

Harney Lake in early August.

Northern Great Basin

The Great Basin’s northern region lies in Southeastern Oregon between the dramatic upthrusts of fault blocks and in sunken basins. Surrounded by miles of dry steppe vegetation zones are many ancient inland seas and lakes. What was once teeming with wading animals, lush tropical trees,and ancient birds are now sun-scorched basins. These dessicated lakebeds with alkaline and sandy soils are the only true deserts of Oregon.

Because the term ‘desert’ is a wide classification of regions that have an annual moisture deficit, such areas can be further categorized as semi-arid or arid. A semi-arid region is a climatic area that receives precipitation less than the combined potential of evapo-transpiration (combination of transpiration via plants and evaporation*), although not extremely. An arid region has a severe lack of available water and where the evapo-transpiration rate significantly exceeds annual precipitation to the extent that normal growth and function of all life is impaired or limited.

Although most of central and eastern Oregon is considered semi-arid, a ‘true’ desert is an area where vegetation is exceedingly sparse and rainfall is also very rare and infrequent. Interspersed amongst the semi-arid steppe lands of the northern Great Basin are isolated lakebeds (playas) that lie within double rainshadows. Precipitation is usually less frequent due to the barriers of the Cascade mountains to the west and tall block fault mountains to the east. Some of these playas may be simply expanses of sand or cracked alkali-encrusted soil, or they may hold seasonal water.

Thriving Watersheds

As the climate warmed, melting glaciers of the Ice Age formed giant pluvial lakes covering much of the Great Basin while rivers carved deep canyons and gorges. Temporary connections between rivers and the lakes may have permitted fish to migrate from the rivers. But, as the climate warmed, the inland lakes dwindled or dried completely. Many of these reservoirs became shallow lakes with feeder streams and fish populations were trapped, where some evolved into unique species.

Most of these basins are closed systems that retain water with no outlfow to external bodies of water. Instead, precipitation draining from higher ranges seasonally feed marshes and playas where they may be seasonally or permanently wet depending on annual evaporation and the presence of springs.

Seasonal and annual water levels depend on a variety  of factors: winter snow pack, rate of snow melt, cycles of drought and rains, and summer temperatures. Typically, water in drainage basins either flows out into larger water bodies or diffuses through permeable rock. However, water in many of the playas in the Great Basin leaves only by evaporation and seepage. Thus the bottom of such basins become salt lakes or salt pan.

Buena Vista marshlands of Malheur National Wildlife Refuge.

Harney Basin: High Desert and Wetlands

At the most northeast corner of the Great Basin region and in Oregon is Harney Basin. Covering 1,490 square miles, it is the watershed of Malheur and Harney Lakes. Both are not true lakes, but playas once divided by a sand dune. Before the sand dune was breached by settlers in the early 1900’s, the Malheur Lake was a freshwater lake, while Harney Lake was saline-alkaline.

The basin receives an average of 6 inches of rain per year, but the surrounding mountains may have 15 inches of precipitation. Both playas receive water from streams originating within the basin in the surrounding mountains, including the Silvies River from the north and the Donner und Blitzen River (often called the Blitzen River) from the south. The watershed of the latter river is the Steens Mountain, which stretches some 50 miles north to south and attains an elevation of 9,733 feet at the summit.

The Harney Basin is considered a part of the larger High Desert Wetlands ecoregion, which consists of high desert lakes and surrounding wetlands. These marshes and seasonal reservoirs provide critical habitat for nesting and migratory birds as well as associated upland birds and mammals. Both Harney and Malheur lakes cycle between open water in wetter years and marshes in drier years. The wetlands around Malheur Lake and the Blitzen River form a wetlands oasis in the basin and has served as habitat for many migratory bird species since before human presence in the Basin.

Malheur Lake and most of the Blitzen River valley are now included in and managed by Malheur National Wildlife Refuge. Each year as many as 320 species of birds and 58 species of mammals can be found in the refuge. Among these, Malheur serves as a Pacific Flyway stop for the Northern Pintail duck and Tundra Swan, Lesser and Greater Sandhill Crane, Snow Goose and Ross’ Goose. Ducks, grebes, pelicans, terns, and trumpeter swans are drawn to the numerous ponds, marshes and lakes. Many raptors, including Peregrine falcons, also call the Refuge home.

This juxtaposition of high desert and watershed with its rich wildlife is indeed a jewel and gem. And one I am grateful to experience this summer.

“Unaccustomed to the desert, we may literally overlook what is directly in front of us. A true irony: not being able to see the desert for lack of trees.” – Alan St. John, author of Oregon’s Dry Side.

 

* Potential evapo-transpiration is the amount of water that would be evaporated and transpired if there was sufficient water available.

High Desert & Great Basin. Part 1

18 Aug

 

It’s been awhile since I have posted here. Not for lack of want, but perhaps too much to write about. Until technology develops a flash drive that can be inserted into my brain and record all my thoughts, I will always be behind. Meantime, I must be selective about writing my thoughts as they jumble and tumble through my head, some of them lost after a moment or two of expression via a smile, snort or shake of my head. Then they dissipate, pushed out by the next train.

Since this blog is primarily about deserts and arid lands, there are boundaries which help determine what I write and publish here. Although I am known to blur the boundaries, sometimes push them, this is not too different from deserts, too. Although humans like delineated and tidy boundaries that help them categorize everything, that is not representative of real life, even non-life. Many categorized zones overlap into what is known as transitional zones. But scientists even attempt to draw borders around those zones. They/we take out our pencils and highlighters and mark boundaries of this zone and that. Not as strict and myopic as politicians and governing bodies, but few ecological boundaries are wanted hard, fast and final. If you step over an international border, you could be shot or jailed. If a plant or bird migrates over a border, well, they are completely unaware of  human borders. Perhaps we could learn a thing or two from them in that respect.

That leads us to a question: what is a desert? It depends on who or what you ask that question of. Nor will I address that question in this post (later post). Several technical delineations define a true ‘desert’ depending on the authority and context. The two common denominators are very low rainfall and evaporation that exceed precipitation (the latter depending on old versus more current definitions). Several journal papers exist that will contest exact definitions of a ‘desert’, which would require a lengthy explanation.  Nevertheless, I will introduce you to a desert that exists in one of those blurred boundaries, the High Desert of Eastern Oregon. Where I am now.

The Great Basin

North America has four major deserts: the Great Basin, the Mojave, the Sonoran, and the Chihuahuan, extending into Mexico. The largest of them, and the northern-most, is the Great Basin. It also has the highest elevation and the coldest winters. The exact area it covers is relatively inconsequential because its boundaries change over time. Regardless, the region covers significant parts of Oregon, Idaho, Wyoming, Colorado, Utah, Nevada and Arizona. The region is typified by its arid climate and basin and range geology. The latter is an integral factor in its climate and geography, and, hence, the rich variety of ecosystems and diversity of life. Thus, an abridged introduction to the Basin and Range physiogeography is necessary to appreciate the complexities and beauty.

Basin and Range

If we go back 200 million years to the Triassic Period and look down upon the continents, Oregon did not exist. It was a long time expanse between the end of the Triassic Period and the current topography of what is called the Basin and Range Province.  Plate tectonics (one of my most favorite earth science topics!), volcanism and glaciers created the Basin and Range as well as the Pacific Northwest. (See the video at bottom of post, courtesy of the Basin National Park)

Like a cracked egg shell, the earth’s crust is made up of large pieces, or plates, floating on its inner soft mantle. These are either continental or ocean plates that have been moving after the planet was formed. This gradual movement is called continental drift. When large sections of these plates collide and grind against each other, they often make themselves known, often with ‘earth-shattering’  effects.

Around 200-140 million years ago (mya) the North American continental plate drifted away from Europe and north Africa, moving westward. By a process called subduction, the oceanic plate moved under the continental plate and sunk into the mantle. Regions where this process occurs are called subduction zones. Often associated with this process is mountain-building, which occurs when large pieces of material on the subducting plate (such as island arcs, or literally, arches of island, like Japan) are pressed into the over-riding plate.

Mountain-building also takes place when subhorizontal contraction occurs in the over-riding plate. Both of these process built the many mountain ranges in the Pacific Northwest.  Firstly,  recurring island arcs were incorporated into the coast line (at one time, the coast line was the current Idaho west state line). Later, block faults rose while tension from plate tectonic movement stretched the surface to the breaking point.

The Basin and Range province was created about 20 mya as the North American plate stretched and thinned. Rock doesn’t stretch,  so it broke into about over 400 mountain blocks that partly rotated from their originally horizontal positions. The spaces in between these giant fault blocks are low valleys, lakes and basins. These mountains of late Precambrian and Paleozoic rock continue to erode and fill the intervening valleys with fresh sediment.

Steens Mountain. A large fault block in SE Oregon.

 

Oregon’s Basin and Range

Over millions of years, the topography resulting in the entire Basin and Range province was shaped and changed by periodic episodes of tectonic plate clashes, volcanism and climate change, including glaciers. Many areas of the province were covered with floods of lava during periods of continental drift and subduction.  The province’s most northern area occupies what is now southeast Oregon. And it was here during a fiery era when lava eruptions and blanketing ash covered most of Oregon east of the present Cascade mountains and resulting in basalt lava plains three miles thick in some places.

During the Pliocene period (5-1.8 mya), the climate in the Northwest became wetter. Run-off and precipitation contributed to sculpting many of Oregon’s river valleys and canyons. Continued volcanic activity in the Cascade Mountains began creating the high peaks and a significant future climatic influence to the east: a rainshadow.

Late in the same period, regional tectonic spreading caused huge areas of the basalt lava plains on the Cascades east side to rise and tilt along the north-south fracture zones. Many of these tilting blocks can be seen today as one sided rims with basalt columns, or giant fault blocks mountains, such as Steens Mountain, Hart Mountain and the Abert Rim. Where two faults run in parallel, the land dropped and formed a basin valley called a graben. Locally, the Alvord Basin sits below the towering east face of the Steens Mountain, whose west side gradually slopes to marshland and the Donner und Blitzen River.

And it is here where begins perhaps the most wonderful juxtaposition of the northern Basin and Range: aridity combined with watersheds that contribute to interesting and delightfully varied ecosystems of plant and animal life. How the two seemingly contradictory biomes interplay is what attracts me to this area, and will be the topic of the next post. And how their boundaries blur annually and seasonally into a kaleidoscope of life and death.

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