Wednesday, October 28, 2015

Collecting my own seed

I've been trying to figure out what to plant in the areas where I've been pulling out the Japanese stiltgrass.  I want to use native plants and I'd like them to be as local as possible.  As I was taking some autumn photos, suddenly it hit me.  Why not use the seeds that my native plants are producing right in my own backyard (duh)!!!  This is perfect.  By collecting seed from around my property I'm getting plants that are adapted to the local area.  I can also make a good guess at where the plants will grow well.  Of course not every seed I put out will germinate but the seeds are free and the investment in labor is minimal.  The seed I am collecting now are from late summer and fall blooming plants.

Here's what I've collected so far:

The ripe seed heads of this Sallow Sedge fell apart into individual
seeds when I touched them making them easy to harvest.

Sallow sedge, Carex lurida, is pretty common on my property.  It forms dense clumps that mature to 2-3' tall and wide.  It grows best in moist to wet soils and partial sunlight.  I have small clumps of it growing in the lawn, but these can't reproduce since they are getting mowed down regularly. The leaves are long and have a deep fold along the midrib.  This gives it a stiff texture.

I'll scatter the seeds along the woodland edges where the soil is moist and there are several hours of good sun each day.  It is also an area where I am trying to remove the invasive wineberry bushes, Rubus phoenicolasius.  The dense clumps may make it a little harder for these bushes to spread.

The seeds of bottlebrush grass are easily stripped off from
bottom to top.  Trying to go the other direction leaves most
of the seed still attached to the stem.

Bottlebrush grass, Elymus hystrix, is a common cool season grass of the northeastern quarter of the US.  Most of the plants I have were purchased, however I have seen some growing remotely.  So I may have some indigenous plants, or they are just really good at spreading.  This species is most noted for the flowers and seed heads that resemble a bottle brush.  The flowers appear in early summer and persist until fall.  

The plants grow from 2 to 5 feet tall and do well partial sun and soils with medium moisture levels.  I will plant these along the edge of a path where the soil drops away.  The height of these plants should still make them easy to see.

The seeds are relatively large.  One ounce typically consists of about 7,500 seeds

Ripe seeds are assisted in wind dispersal by the fluffy white appendages.
Some flowers still in bloom are at the lower right in the photo.

Tall Snakeroot, Ageratina altissima, formerly Eupatorium rugosum, is very common in this area.  It is particularly evident in my area along roadsides near the Potomac river.  It grows well in full to partial sunlight and a range of soil moistures.

It is tolerant of soil disturbance, making it a good candidate for an edge habitat where plants are occasionally mowed down.  I'll scatter these in some of the drier woodland edge areas.

The seeds are tiny, typically 150,000 per ounce. They require light for germination.  This is common for disturbance adapted plant species.

Here most of the fluffy seed of the Sweet Everlasting have 
been blown away, leaving the sepals as 'everlasting' flowers.

Sweet everlasting, Pseudognaphalium obtusifolium, is a native annual that depends on disturbance for survival.  It is most common recently cleared areas in full sun and dryish soils.  I have a recently cleared meadow area that will be perfect for these.

This plant is evident in a border because the fine hairs on the leaves and stems catch the sunlight and make it look like the plant is glowing.  The tiny white flowers never fully open but form white clusters of buds that show well.  After blooming long-lasting bracts remain giving the effect of an everlasting flower.

The seeds of this species are really tiny, coming in at 500,000 per ounce.  It is hard to find the actual seed, there is so much fluff attached. These seeds are quickly wind dispersed, so I need stay on top of harvesting them.

Short's Aster, Symphyotrichum shortii, is found in the mid-Atlantic and mid-western states.  This aster is the latest blooming species that I have growing.  It starts in about mid-September and continues to the end of October.  Besides its long and late blooming cycle, it is also tolerant of dry shade and alkaline soils.  This makes it an excellent candidate for deeper into the woodland areas where it can compete with the stiltgrass for patches of light and openings in the canopy.

Each seed of Small's Aster has an attached pappus that looks like a little umbrella that catches the wind.  The actual seeds are larger than the previous two species, with about 60,000 per ounce.

In the center are some ripe seeds with their fluffy pappus.
In the background you can see some or the lavender
flowers still in bloom.
So these are some of the later blooming species that I will try to 'seed' into the stiltgrass infected areas.  There no reason I shouldn't harvest some of my spring and early summer species and do the same.

Tuesday, October 13, 2015

Stiltgrass management, part 2

After trying to remove as much Japanese stiltgrass as possible in late summer, the next step is to fill in the gaps with more desirable plants. My approach last year of seeding in native grasses like Canada and Virginia ryes did not work out too well.  There were some good reasons for my disappointing results.  I needed to plant  these relatively large seeds more deeply to get better germination.  Also these new grass seedlings need 2-3 years to establish before mowing back, or using as pasture.  It would be better to use these big perennial grasses in a meadow planting where mowing is done only once a season.

This year I am trying a more conventional route with the filler grasses.  I will be using commercial turf grasses that are selected for rapid growth and formation of a dense turf layer.  This is what I need to exclude the stiltgrass.  By planting these cool season grasses in the fall they have a chance to germinate and fill in before the stiltgrass starts growing in mid-spring.

I divided up the stiltgrass infected areas into full sun, part sun and mostly shade and selected a seed mixture appropriate for each condition.  For full sun I selected a blend of tall fescues with just a little Kentucky bluegrass.  For the part-sun areas I have a blend or both tall and fine fescues with a little perennial rye and Kentucky blue grass.  For the shade areas I am using a blend of fine fescues selected for low maintenance.  This year I am using Eco-Grass from Prairie Moon, but there are other blends such as No-Mow from Prairie Nursery and Eco-lawn from Wildflower Farm that should work as well.

Most commercially available cool-season turf grasses are not native to North America with the exception of some of the fine fescues, in particular red fescue (Festuca rubra).  You can find detailed information about which turf grasses are appropriate for your region from your state's cooperative extension.  For example the Maryland Extension Service has a listing of recommended grass cultivars that were tested locally.

Before buying seed this year I shopped around to see what specific seed cultivars were used in each of the blends.  There is usually a tag with the detailed seed composition somewhere on the bag. When I went out to buy the one I liked, I found that that specific blend was no longer available even though the product name on the bag was the same.  Frustrating!!!  I imagine that the retailers are still trying the produce an equivalent performing product, but it still, that was a frustrating experience.

The first step in the reseeding process is to remove the stiltgrass thatch in the lawn.  This opens up spaces for the new seed and may help remove some undispersed sitltgrass seed.  Since late in the season much of the remaining stiltgrass has had a chance to set seed, this thatch needs to be segregated from regular compost and the regular brush piles.  I have a couple of piles dedicated to stiltgrass so that it does not get mixed up with the regular yard waste and I can monitor it for spreading.  Another option would be to landfill it in thick plastic bags.  You do not want to let the stiltgrass get out and spread its seed.

Late September is when the stiltgrass begins to die back.  The brownish areas are easy to spot.
Once the area was clear of thatch I applied the new seed.  I used the back side of a bow rake to press the seed into the soil.  The nice thing about the conventional turf seeds is that they do not need to be planted deeply.  After sowing, it is necessary to keep the new seed bed moist until the new seedlings are established. I usually try to time my seed sowing with coming rains.  That way I don't need to water it in (I'm really lazy in that way).  Besides the cooler temperatures, autumn is a good time for lawn seeding because it is usually a rainier then too.   I usually see good levels of germination in 10-14 days for the Eco-grass.  This year is working out well (so far).  The soaking rains in early October saturated the soil and I have only needed to add a little additional water to keep the soil moist.

The area between the piles has been (mostly) cleared of stilt grass and is ready for seeding.
I used a leaf rake for this, but a stiff garden rake would have been
more effective for tearing out the stiltgrass plants.
While the standard instructions on the seed bag recommends fertilization at the time of seeding, it is best to do a soil test to determine if added fertilizer is needed.  If you use a mulching mower to return your grass clippings and leaves to the soil your fertilizer needs will be much lower (or non-existent). The risk of over-using fertilizer is that it will stimulate weed growth and that run off of excess nutrients will damage the environment.  Since we are in the Chesapeake watershed I try to use the minimum of fertilizer possible.  That usually means none.  In fact, for the fine fescues fertilization is not recommended.  If fertilization is needed, fall is the best time for cool season grasses.  Spring fertilization will stimulate growth of warm season weeds (and stiltgrass) as well as the cool season grasses.  In the fall only the cool season plants are actively taking up nutrients.

In this full sun area tearing out the stiltgrass exposed a lot of bare ground.
This spot was seeded with the full sun blend.  Just to the back left
 is a full shade area where I planted the Eco-grass mix.

One new thing I learned about tall fescue, Lolium arundinaceum, is that some cultivars are infected with an endophytic fungus that produces loline alkaloids that are toxic to many insects and mammals that feed on the grass.  This endophytic fungus also reduces biodiversity around the infected fescue.  while this is great for the fescue it is bad for the wider plant and animal communities.  The widely used and inexpensive cultivar K-31 has a high rate of infection.  So far I have not been able to find out which cultivar have low infection rates, however this may be more common in southern states.  One way to lower the effects of infected fescue on the environment is to keep it mowed so that it stays in a vegetative state, i.e., not going to seed.  Hopefully its ability to form a good turf and exclude the stiltgrass will outweigh it negative environmental effects.