Month: May 2019

28 May 2019

What is Bulk Density?

What is Bulk Density?

Ask people what a plant needs to grow and you will probably get answers such as, “sun, water and soil”.  The soil provides important nutrients (and fungal associations) to the plant, but also needs to have right physical properties to allow a root to grow and penetrate. The physical growth of the root is quite dependent of the soil in which it is trying to grow.

One important measurement in determining the ability for a root to penetrate the soil is bulk density.  Bulk density is the weight of dry soil per volume (grams/cm3).  This value reflects soil texture and compaction.  In addition to affecting the ability of a root to grow, bulk density will affect infiltration, water capacity, porosity, nutrient availability and soil microorganism activity.

Bulk density can be measured by collecting a known volume of soil and then measuring the dry weight of the soil.  At Greenacres, we use one of two methods, depending on our location.  In the pastures, easily accessible by the soil probe, we can collect a sample in a plastic sleeve.  The tube is then cut into known lengths to determine volume and the soil sample dried.  In the woods, we collect the sample by hand by driving a cylinder (known volume) into the ground and collecting the sample.

Table 1 compares some bulk densities across Greenacres properties. In general, bulk densities below 1.6 grams/cm3 are good for root growth.  The soil in Lewis Township is more compact and has a higher bulk density compared to the pastures at Indian Hill.  The management of these soils contributed to this difference.

Table 1.  Bulk densities were measured across 3 Greenacres sites: Beech Maple Woods, Front Nippert Pasture and Lewis Township field.

Location Bulk Density (grams/cm3)
Beech Maple Woods (transect 1) (0-10 cm) 1.05
Front Nippert (pasture) (0-10 cm) 1.1
Lewis Township (historically soybean field) (0-10 cm) 1.61

 

–Jennifer

14 May 2019

Fairy Umbrellas

I like to call these fairy umbrellas. Perhaps my mind is in vacation mode, but they remind me of a crowded beach. I like to imagine all of the little fairies posting up in their favorite woodland area to enjoy a day of relaxing. Maybe in the late summer when the fruit develops, they use it to play a game similar to beach volleyball…

Would you believe that the majority of these plants (see pic 1) are actually from one individual? That’s right, American Mayapple (Podophyllum peltatum) is a rhizomatous perennial, reproducing asexually by means of rhizomes underground. It’s one of the first early spring wildflowers in Ohio, often found in shaded woodland areas. Mayapple is hard to mistake for many other wildflowers because of its large rounded leaves and colonial growth. The shoots that grow vertically, producing the colony above ground, consist of either one leaf (asexual) or two leaves (sexual). A lone flower is produced in the axil of the plants with two leaves, usually in May (see pic 2). This plant does not appear to be trying very hard to attract pollinators with its inconspicuous flower placement, but even more perplexing is that the flower lacks nectar! The pollen produced does in fact attract some native bees and bumblebees. Thus, because Mayapple is extremely unlikely to self-pollinate and is lacking in its sexual reproduction design, the majority of the energy goes into rhizome growth, creating a highly clonal species.

Mayapple stays in suspiciously pristine condition compared to neighboring plants full of insect damage. That’s because the majority of the plant is poisonous. In fact, podophyllotoxin can be extracted from the rhizomes or leaves and used medicinally for cancer treatment. The only edible part is the berry, but even then you need to avoid the seed and the skin. If the flower is pollinated, a small lemon shaped berry is produced by August. Some mammals and birds are known to eat the berry, but the primary Mayapple seed disperser is the unsuspecting Eastern box turtle. Even slower than a turtle, if a seed successfully disperses to a new area to grow, it is believed to take around five years to mature to produce rhizomes! I sure do love the image of a box turtle munching berries in the shade of mini umbrellas. Would the turtle be considered a pet to the fairies? Would it cause pandemonium like Jaws? I encourage you to go on a hike in search of these flowers currently blooming and again in late summer for the berries. Who knows, maybe you’ll come across a fairy or even a box turtle!

~Tracy

10 May 2019

“The Best Laid Plans…..”

“The Best Laid Plans…..”

We were so excited to begin our controlled experiment looking at the horses pastured with and without chickens.  The pasture was chosen, the chicks were reared and a smaller mobile coop was constructed.  We did not anticipate that the chickens would be reluctant to leave the coop and forage in the field.  We suspect the chickens may be too young to begin foraging and this has disrupted out experiment.  The equine department will continue to monitor ticks to collect data on numbers and will also collect data on the chicken behavior.  This information will be used to strengthen future experiments.

–Jennifer

01 May 2019

Where the Wildflowers are…

Where the Wildflowers are…

Being in the woods daily has given me a perspective on spring ephemerals that I have not experienced before.  In the past, I would generally hike in the woods around April and “see what was blooming”.  This year, I watched leaves emerge from the ground and in some cases knew exactly what flower was coming, but in other cases I had to wait several weeks for a flower in order to identify the species.   The mottled waterleaf leaves emerged early but I saw no blooms until May. In some cases, I was waiting for a bloom that did not arrive (wild leeks- thank you Team Nature for that tip).  Mayapple poked up its stems over the course of one weekend and I missed the bloodroot flowers completely.  But now I have a better sense of what wildflowers are on the property and where they are blooming.

–Jennifer

Yellow trout lily blooming amid the invasive lesser celandine.