Geese at Bittersweet Park. Photo by D. Sillman
(Click on this link to listen to an audio version of this blog … A walk around Bittersweet Park part 2
(This a continuation of the mid-February walk around this large, city park in Greeley, Colorado) that Marian, Lee, Deborah, Ari and I took to savor a spring-like burst of weather!)
Today was the second day of the annual Great Backyard Bird Count, so I took fifteen minutes as we stood on the walk above the lake to count birds. There were eighty-five Canada geese sleeping on the opaque ice of the lake (and just after I counted them and my allotted fifteen minutes had expired, at least one hundred more geese flew in for a noisy reunion with the lake dwellers!). Floating on a small circle of open water at the south end of the lake were twenty-four ring-billed gulls and two mallards. Later, I saw an American coot (but this was after my bird-count time had elapsed). In the tall grasses and reeds over on the west side of the lake five, male, redwing blackbirds flew from vertical perch to vertical perch trilling and calling out as they claimed mating territory in anticipation of the arrival of the female blackbirds (probably a week or two from now!). In a line of cottonwood trees up near the sidewalk along the west side of the lake, three northern flickers called and flew from high branch to high branch. They were also probably thinking about mating, but it is almost spring isn’t it?
Photo by D. Sillman
I had previously mentioned to Marian that mud seemed to be an uncommon substance out here in northern Colorado. She and I reminisced about the muddy expanses that would regularly form after a heavy rain or after a snow melt in our yard and field back in Pennsylvania. We remembered losing shoes and boots in the sticky mud and getting our car stuck in our “grassy” parking spot before we added a couple of tons of gravel to it. We remembered our dog, Kozmo, racing around in the muddy yard with her chocolate lab friend, Penny, throwing spatters of mud up onto the side and roof of the house.
Mud!! All of the snow melting around my house here in Greeley was ringed with rapidly drying soil! The dry air and the intense sun almost immediately dried the mud in place. I am very glad to report, though, that the dirt trails on the east side of Bittersweet Lake were very properly muddy and full of puddles from the recent snow melt, and that mud puddles, even when especially rare, are greatly cherished by two-year-old, little boys!
Ari got soaked playing in the puddles as we walked around the lake. He splashed the muddy water high up onto his pants and coat. His shoes filled up with cold water and his socks were icy and disgusting! He was so happy!
Photo by D. Sillman
The blue spruce (Picea pungens) is the state tree of Colorado. It has a remarkably limited, mountainous, natural range but has been extensively, although not always successfully, planted all around the world (see Signs of Summer 12, August 3, 2017). Appropriately, there were several blue spruces planted around the periphery of the lake. All of these trees were growing in dense, conical shapes with their thick branches drooping down to the ground to form the walls of variously sized enclosures. The ground inside these enclosures was covered with shed spruce needles and due to this mulching and extreme shading by the tree, was virtually plant-free.
My old house back in Pennsylvania had a dozen or so blue spruces that had over the decades grown into a continuous stand with interconnected, sheltered spaces beneath their branches. My children called these their “forts,” and they were the stages for long summer games and great expressions of their imaginations.
I wondered if anyone ever played in the “forts” under the spruces here at Bittersweet Park? The spaces would also be great places for animals to hide out during the heat of a summer day and for sun-sensitive (but mulch tolerant) plants to find some respite from the intense conditions of our northern Colorado summers.
Photo by D. Sillman
The spruces were covered with cones! The branches in the first 2 or 3 feet of the tree had dense masses of small, pollen (“male”) cones, while the branches from 3 feet to the near the top of the trees were covered with large, seed (“ovulate” or “female”) cones. The arrangement of putting the pollen cones below the ovulate cones is a simple mechanism to reduce the chances of a tree fertilizing itself! The wind-blown pollen tends to spread out away from its tree of origin and then, if ever does find a receptive cone, that would most likely be some other tree’s ovulate cone. Thus, the great scrambling of genes that is the point of sexual reproduction would occur!
Photo by D. Sillman
There were also several lines of cottonwood trees (Populus deltoides) scattered around the grassy areas of the park, and their branches were covered with buds. There would be a bit of wait, though, before any of these buds open. The flower (“catkin”) buds will open first revealing the “male” cottonwood trees (densely covered with fat, red, pollen producing catkins) and the “female” cottonwood trees (less densely covered with slender, green, ovulate catkins). The pollinated ovules will swell over several months developing the eponymous “cotton” seeds of the species which are then released in great seed clouds in early summer.
Photo by D. Sillman
Leaf buds of the cottonwood open after the flower buds and reveal a very interesting pattern of leaf production (a “heterophyllous” system of leaves). The first leaf unfurled from the bud is called a winter leaf (or “preformed” leaf). This leaf will begin photosynthesizing immediately in the spring and supply the early season energy needs of the tree. Then, as summer approaches, a second leaf generation event occurs in the buds with the formation of the slightly larger and more extensively toothed summer leaves (also called the “neoformed” leaves). These neoformed leaves will then photosynthesize through the summer season and will be the last leaves shed from the tree in the autumn.
Photo by D. Sillman
Growing near the parking area was a large eastern red cedar (Juniperus virginiana) (which, as its genus name tells you, is really a juniper and not a true cedar). The bark of this tree was arrestingly beautiful: it was a glowing reddish brown that was divided into twisting, interlaced fibrous shreds that wrapped themselves up and around the trunk. The ground under the cedar was covered with tiny, dry, round seeds that may have been the shed seeds from the berry-like cones or maybe the dried cones themselves. Many birds and small mammals feed on cedar cones. The cedar waxwing, in fact, gets its common name from its penchant for feasting on the cedar “berries.”
The natural range of the eastern red cedar is a subject of some debate, and at first it seemed to me to be unusual to see this tree to be here in Greeley Colorado. Many references limit the eastern red cedar to the 37 states in the eastern and midwestern sections of the United States with some extension into southern Canada. These tree guides state categorically that the eastern red cedar is limited to the USDA Hardiness Zone 7 (and higher) and, thus, won’t grow in Colorado (where Zones 6, 5 and 4 predominate). Colorado plant lists, though include the species and it was noted that there is a record sized, eastern red cedar growing in Denver! Confusing? Yes!!
The eastern red cedar is closely related to the Rocky Mountain juniper (Juniperus scopulorum) which grows in the rocky soils of nearby mountains (all the way from southern New Mexico to British Columbia). The two species are said to extensively hybridize along the line where their ranges meet (possibly right here in Greeley?).
The eastern red cedar is very drought tolerant and widely planted as a landscaping tree around the world. In some places these “domesticated” eastern red cedars have “escaped” into the wild (seed transport by cedar “berry” eating birds?) and have resulted in the eastern red cedar becoming a destructive, invasive species. Looking at the abundance of potential seeds on the ground around the tree, one can easily see the species great reproductive potential!
We had a great spring walk around Bittersweet Park right in the middle of winter! I am sure that we will come back for more!