Monday, June 30, 2014

Early summer flowers in Tandy Prairie

Ruellia humilis, with a purple bee-highway
I like to return to prairies to keep tabs on how the are moving through the year. Last weekend, I visited Tandy Prairie. I'd first visited in late April. At that time, the meadows were dotted with prairie hyacinth, cobae penstemon, and other ephemerals. By late June these ephemerals were gone.  Most of the blanket flower had gone to seed, but the horse mint and mid summer flowers had popped up in bloom

Don't mind me...
Tandy Prairie is a remnant just a few miles east of downtown Fort Worth. It's a very small parcel, but it has retained some interesting flora. The soil on the ridge tops was just a shallow dusting over limestone, similar to the late vacant-lot prairie. I can't help but wonder if the poor soils helped the native plant community resist invasion.

I saw (and, unfortunately, couldn't resist impinging upon) some interesting bug life. The ubiquitous bee assassin was lurking under horse mint, a lone Bombus pensylvanicus was foraging among the basket flowers, and two skippers were ensuring the continuation of the species. Ahem.

I can't imagine an efficient means to manage such a small parcel. I know this place isn't without problems- the creek bottoms are choked with privet- but it is still a lovely little patch in the heart of the city. It has some Texas-endemic species, including bluebonnets and the white compass plant (Silphium albiflorum).  While the more widely distributed compass plant's (S. laciniatum's) foliage is highly palatable and rapidly disappears in a pasture, the leaves of S. albiflorum are a little more bristly and (anecdotally) are less favored by cattle.

Happily, this 160 acre prairie has its own group of defenders, Friends of Tandy Hills Natural Area. Here's hoping it can continue to thrive with their care and protection.

More pictures after the jump.

Sunday, June 29, 2014

Blooming five-angled dodder (Cuscuta pentagona) in Tandy Prairie

Blooming dodder, heavily parasitizing its host.
The family Cuscutaceae, formerly lumped with the morning glories (Convolvulceae), are a very unusual bunch. These plants are parasites. They don't produce their own chlorophyl, so they survive by by tapping the phloem of a host. They can tap multiple plants at once, and can serve as a disease vector, spreading viruses from one individual to another. I was excited to catch this piratical plant in bloom in Tandy Prairie last week.

You can see a little bit of the host's yellowing in the photo above, but it was much more extensive than I captured in that image. Seems like a bad parasite, right? To kill your host? But I suppose if the dodder can tap a new host once its old one expires, then perhaps it doesn't have to be so committed to only taking what can be spared.

Funky flowers, closer up.

Interestingly, dodders start with a root, but it dies off once they find a host. They grow airborne. These plants are so totally committed to parasitism, their seeds don't come provisioned with cotyledons.

Apparently, these plants even have what could be called a sense of smell.  When they germinate, the seedlings sniff the air and grow towards volatiles coming off a suitable host. For example, in one experiment they preferentially sought tomatoes 73% of the time. Weedy or not, I think I love this little plant. It is so weird.

Sunday, June 22, 2014

I have squash bees!

Morning in my three sisters garden. How many blurry bees can you spot in this picture?
I am delighted to report that native squash bees have found my three-sisters (squash-beans-corn) garden. Squash bees, as you might surmise, only collect pollen from squash blossoms. Their genus is native to North America. Before the introduction of old-world squash, they fed exclusively on new world domesticates and the wild Cucurbita foetidissima (buffalo gourd). I *believe* the species visiting my winter squash is Peponapis pruinosa, but it is hard to tell. These hyperactive bees would only settle for an instant before flitting off again. It made me wonder if most of the bees circling my garden were males. In bees, this patrolling behavior is more typically male. Females are working hard to provision their nests, while the males are working hard to find females.
Peponapis pruinosa butt

Squash bees are interesting for a number of reasons. For one, they are a species that has actually expanded its range with human influence. Because these bees can only feed on squash, once humans domesticated squash and introduced it far beyond its original range (southern plains to the southwest), the squash bees followed suit and expanded their home region. The females often dig their nests directly under squash plants, and the males sleep in squash blossoms at night. Another interesting fact: because squash blossoms open before dawn and close a few hours later, squash bees have adopted the same crepuscular pattern of activity. They fly well before most bees wake.

In addition to the squash bees, I've seen number of fuzzy, medium sized black bees. I have no idea about their genus, but they visit the squash blossoms as frequently as the squash bees. I am so pleased that these helpful creatures are ensuring my gourds and melons are well pollinated this summer, and I'm sure they are happy for the meal.

Mystery black bee, blurry Peponapis pruinosa trying to run her off

Sunday, June 15, 2014

Bugs and Slugs at Cedar Creek Preserve

Standing Cypress viewed through my new macro lens
Since the passing of the vacant-lot prairie, I've seen wildflowers like purple ruellia (Ruellia nudiflora), standing cypress (Ipomopsis rubra), and basket flower (Centaurea americana, described in a previous post) pop up in nearby weedy areas. I'm still trying to get a feel for the local calendar of plant life as it blooms and fades over the season.

bluebonnets prairie bluets and tiny bug with eyes like a fly
This has been a banner year for gaillardia and basket flower.  Both are opportunistic annuals that have benefitted from the remarkable drought Texas experienced over the past few years. When perennial plants are weakened, annuals are released and find the space they need for germination. Generally, I prefer perennials for their dependability, but annuals can also make great insectary plants.

oak 'apple' gall
This part of the world (probably all parts, actually) is full of insect life. Much of it is benign, some definitely is not, and others are still a mystery. Every time I walk through shrubby red oak thickets I see these galls pictured to the right.  Sometimes an oak is so well decked out in these round ornaments that it looks like it's fruiting, a natural growth of the tree. In truth, it's a nursery for a gall wasp (possibly Amphibolips confluenta). The habits of the gall wasps are still somewhat unknown to science. They spend most of their lives as larvae underground, emerge for a brief period to mate, and then senesce and disappear again into the oaks and the earth.  People used to use oak galls to make ink for quills used on parchments and vellum. The gall was combined with iron and an acid, which then produced purple-black ink that darkened as it dried. You can make something similar today by soaking iron nails in vinegar and then mixing it with an oak gall decoction.

Helpful unidentified snail, feeding on common hedge parsley (an invasive)
The land snails in Texas also have an interesting socio-cultural history.  I've generally overlooked land snails, but I've learned that they've got their own food web going on. Some snails are specialist predators on other snails and slugs. Other snails are major vectors of human disease. Texas has had brushes with more than one of each category. 2013 was the year of the Texas African Land Snail scare. African land snails can live for almost a decade, can reach the size of a rat, and have no predators here in the States. You may wonder: "What's the big deal about a big snail?" Well, African land snails carry a parasite that causes meningitis in humans.

The African land snail invasion has since been debunked, but other exotic snails have been established in Texas. One example is the decollate snail (Rumina decollata), originally introduced in Arizona for bio-control of the brown garden snail (Helix aspersa), also introduced from the Mediterranean. Humans have made the brown garden snail a global species. Sometimes we eat them with garlic and butter.

I had never given much consideration to the origin of the snails in my garden, but it turns out many of them are present due to human intervention. The same can be said of the "roly-polys" of my childhood- they too are introduced. It's strange to think that the basic wallpaper of my outdoor life is a relatively new to this landscape.

Wolf spider, watching me watching her.

Saturday, June 7, 2014

Death of a Prairie

It's all gone. I left for work travel on Monday, and when I opened the blinds to let in the sunshine Thursday morning the vacant lot prairie had been scraped clean, down to mineral soil. Not even the seedbed remains. Only the few live oaks linger. It used to be, after all, a remnant oak savannah.

The efficiency of this near-total obliteration is shocking. I'm not mad-- not exactly. Not at the construction workers anyway. I knew this land was likely to be developed in time.  I didn't own it, and it wasn't a park. It's the speed of the shift that is upsetting. This was original, unplowed, native prairie. It had managed to hold out in an urban center for over a hundred years. Then, after discovering this prairie in May, it was gone by early June. It is such a strange twist of fate that after persisting so long without notice, I should stumble upon it, begin documenting its flora, and then lose it all in a month. I bet no one had ever performed a floristic survey there before, and now I have one just in time to list what we have lost. What bitter herbs.

The greatest hurt to me is the destruction of this genetic reserve. At a few acres, this parcel was too small to harbor a functioning ecosystem, but the bones- the plants- were there. I didn't manage to save so much as a seed. I kept telling myself they'd be ready for collection in a week, and that I'd gather them next weekend. I hate digging up native plants- to me it feels like vandalism. Now I am filled with remorse that I couldn't save anything. This is the true heartbreak. If I had been in town when the clearing started, perhaps I could have performed a salvage operation. 

In the month that I knew this little prairie, I identified 25 blooming native wildflowers, many of which were atypical to the region. Who knows else we've lost? If I'd been given a full growing season instead of just a brief window, what would I have found? If the prairie had persisted until the fall, what genetic gems might I have saved?

Last green thread growing near the new fence
I mourned the passing of my prairie to a friend over the phone, and she said that perhaps what we can take from this is that anything not explicitly protected is under threat.  The destroyers do not do so out of malice, just out of a kind of blindness. A forest, a prairie, a stream may look permanent, but everything is transitory. We cannot afford to be complacent.

Ideally I would see this loss as a call to arms. Ideally, I would drive around Fort Worth, find other lots, and save what I can. Be more ruthless about plant collection. Convert my front yard into a native plant preserve (not a bad idea, and I'm working on it). But I feel tired. It is easy to retreat, to spare my sensitive heart and love only what is already protected.

But I will be dogged in my search for these little remnants. I know I will continue to seek out these special places. I will seek them out with a visceral understanding of their vulnerability, and I will document them for posterity because not even knowing what we have lost is the greater tragedy.

The final plant list:

Latin Name Common Name Date Observed
Asclepias asperula antelope horn 17-May
asclepias viridis green antelope horn
Cooperia drummondii evening rain lily 17-May
Cooperia pedunculata hill country rain lily* 17-May
Dracopis amplexicaulis clasping leaf coneflower 28-May
Engelmannia peristenia engelmann daisy 17-May
Gaillardia pulchella indian blanket 17-May
Gaura coccinea scarlet gaura 17-May
Glandularia bipinnatifida prairie verbena 17-May
Helianthus ciliaris texas blue weed 22-May
Krameria lanceolata ratany 17-May
Lantana urticoides lantana 17-May
Lupinus texensis texas bluebonnet 17-May
Lysimachia lanceolata lance-leaf loosestrife 28-May
Mimosa nuttallii sensitive briar 17-May
Monarda citriodora horse mint 28-May
Neptunia lutea yellow-puff 17-May
Oenothera speciosa pink ladies 17-May
Phyla nodiflora texas frog fruit 17-May
Polytaenia nuttallii prairie parsley 17-May
Ratibida columnifera prairie coneflower 17-May
Senna roemeriana two-leaf senna 17-May
Solanum carolinense carolina horse nettle 17-May
Stenaria nigricans var. nigricans diamond flowers 17-May
Thelesperma filifolium green thread 17-May
Tradescantia occidentalis western spiderwort* 17-May
Verbena halei texas vervian 17-May
Trying to end on a positive: native lantana growing near railroad tracks.

Tuesday, June 3, 2014

Wheelbug Instar

Junior wheel bug, Arilus cristatus
I've been wanting to post this picture of a wheel bug larva for a week or two, but I was hoping to get an image of an adult to pair with it. Well, adult wheel bugs aren't flinging themselves out of the bushes to be photographed (the little guy or gal pictured above played a long game of ring-around-the-coneflower with me before I could even get that shot), so I'm going to proceed without a visual comparison with the final morph. Until I get my own picture, you can click the link below to view the adult version.

image of two adult wheel bugs on flickr

Adult wheel bugs are totally distinctive. They are the only North American insect with a characteristic raised crest behind their heads. They are also quite shy. If noticed, they generally attempt to scurry out of sight, ducking beneath leaves and twigs. Wheel bugs are excellent garden insects. They are fierce ambush predators, and they especially savor caterpillars, beetles, and aphids.

Man and beast alike would be well advised to leave wheel bugs to their business. Over at SFgate, Richard Fagerlund compared being bitten by a wheel bug to being shot. Richard has, in fact, been shot. I figure he know's what he's talking about. The pain lingers for a few days, and some victims report numbness in the area that eventually subsides.

Despite their immense capacity to deal out pain, I'm glad to have wheel bugs around, and doubly glad they're surviving in my urban prairie. This unique insect is the tiger of its miniature forest.

Sunday, June 1, 2014

A hot morning at Marion-Sansom

Chafer beetle burrowing into a basket flower
(sorry about pic & vid quality- all taken by iPhone in this post)

I've decided Marion-Sansom is my favorite local park. It's not for everyone- when I visited this Sunday morning there was plenty of (relatively benign) illegal activity. Marijuana smoke crept around the trees, and a group of drunk fishermen took pot shots at a water snake with an airgun. However, there were also packs of mountain bikers, two women trail running, and a large family out for a Sunday hike. Mom was trying to get the kids jazzed about all the butterflies.

Lovely shelf-falls below the dam

Marion-Sansom is a little more wild and wooly than its across-the-reservoir neighbor, the Fort Worth Nature Preserve (another park I adore), but it has a similar cross-section of the "Grand Prairie/Cross Timbers" flora.  Fort Worth Nature Preserve also has bison, prairie dogs, and well-marked and maintained trails.  Marion-Sansom has 11 miles of single track solely maintained by a mountain biking club.  I was actually greeted by a member of the club.  He said people kept vandalizing the trail map posted in the parking area, so instead he gave me directions to the major waterfall below the dam. There's something about people who are intensely into their hobby- they tend to be eager to share their work. Outdoor enthusiasts of all colors have a special corner of my heart. Another note: Marion-Sansom is free to the public, while Fort Worth Nature Preserve finances its amenities with a $5 admission fee.

My terrifying hound, smiling.
So why do I like Marion-Sansom? Well, for one, the drunk fishermen had terrible aim and were afraid of my dog. More importantly, it is a genetic reserve of local plant diversity in my backyard.

I have never seen so many basket flowers!  The limestone bluffs above Lake Worth (a product of the dammed-up West Trinity River) were covered in them, and also diamond flowers and yucca. The rocky slopes were also spotted with horsemint and the tail-end of the blanket flower blooms. There were more flowers than grass.  I also saw my first wild-growing prairie clover since moving to Texas. I found it amongst another decorative native- Texas grama (Bouteloua rigidiseta).
Purple prairie clover and Texas grama

This park seems like it should be a bee paradise, and there was plenty of invertebrate life buzzing around. Dragonflies, butterflies, chafer beetles, honeybees, and bumblebee mimic flies and moths were happily flittering through the open hillside. Despite the evidence of bumblebee-mimics, there were still no bumblebees. Even the purple prairie clover, which should be a bee-magnet, was bare of native bees. Where are they hiding?

The only natives I saw were frantic male carpenter bees patrolling their turf for females. If you've got a mean streak, you can get their desperate little hopes up by throwing bee-sized objects in their direction. They'll chase down your pebble, ascertain its gender, and then return to their perch (presumably disappointed). So, other than a few girl-crazy carpenter bees, I didn't see much in the way of native bee fauna. Too bad. I'll keep looking, and I'll certainly return.

More images of the invertebrate life in Marion-Sansom after the jump.

They do kind of look like woven baskets...