Issue 8, June 23, 2014
Illinois Invasive Plant Phenology Report
Several invasive plant experts from around the state have started a new series of reports focusing on the phenology of invasive plants in Illinois. The intent of these reports is to provide an update on the development of invasive plants across the state of Illinois -- what plants are in bloom, leafing out, setting seed, or senescing in different areas of the state.
Readers are encouraged to share what they see in their area of the state by emailing Chris Evans, Invasive Species Campaign Coordinator of the Illinois Wildlife Action Plan (chris.evans@illinois.gov).
Phenology Report for May 16, 2014
(Contributors include Cathy McGlynn, Karla Gage, Marilyn Leger, Eric Smith, Mike Davis, Matt Baulk, Paul Bane, David Crady, and Mike Daab)
Southern Illinois
- Garlic mustard, Alliaria petiolata - Second-year plants are senescing, becoming chlorotic; siliques have matured and seeds are hardening. Seeds have not yet begun to dehisce as of June 3. Once this occurs, contact with the plant is not advised because seeds are easily spread.
- Bush honeysuckle, Lonicera maackii and L. morrowii - Amur honeysuckle has passed flowering stage and the fruits are beginning to form, still small. Morrow's honeysuckle has bloomed and now has bright red and orange fruits.
- Japanese honeysuckle, Lonicera japonica – Japanese honeysuckle is in full flower now.
- Border privet, Ligustrum obtusifolium - Flowering stage has passed peak and fruits are beginning to form.
- Purple wintercreeper, Euonymus fortuneii- Plants that have enough available light (high in tree canopies or in open wooded edges) are producing flower buds.
- Chinese yam, Dioscorea oppositifolia , syn. D. oppositifolia - Plants are beginning to produce flower buds. The beginning of bulbil production still has not been observed. Plants are climbing rapidly into the tree canopy as new plants continue to emerge from last year's bulbils.
- Teasel, Dipsacus follonum and D. laciniatus - Teasel is bolting and almost at the stage of flowering. In fact, you could likely find a few plants already in flower
- Japanese stiltgrass, Microstegium vimineum – Stiltgrass is 4-5 inches tall and getting ready to start its rapid summer growth. Look for it to rapidly increase in height over the next few weeks.
- Poison hemlock, Conium maculatum – Poison hemlock has been in full flower but many of the flower heads are starting to fade and produce seeds.
Southeast Illinois
- Yellow sweet clover, Melilotus officinalis – Yellow sweet clover is in full bloom
- Crown vetch, Securigera varia – Crown vetch is in full bloom, along with hairy vetch, Vicia villosa
- Cypress spurge, Euphorbia cyparissias – Cypress spurge is in full bloom
Central Illinois
- Garlic mustard, Alliaria petiolata – Plants are starting to have darkened seed pods.
- Wild parsnip, Pastinaca sativa – Wild parsnip is in full flower right now and we have pulled a few that were passed flowering and had immature seeds.
- Poison hemlock, Conium maculatum– Poison hemlock is in full bloom but seeds have not been observed yet.
- Reed canarygrass, Phalaris arundinacea – Some heads starting to produce seed but all are still light and immature, most are flowering, and some are just sending out their flower stalk.
- Canada thistle, Cirsium arvense – Canada thistle is starting to flower fully now. Bull thistle, Cirsium vulgare, is still low to the ground without much of it shooting up the center stalk yet
- Japanese honeysuckle, Lonicera japonica– Vines are just starting to flower in a few areas.
- Crown vetch, Securigera varia – Crown vetch has been flowering for a few weeks now, though there is still time yet before it develops seed.
- Yellow sweet clover, Melilotus officinalis –Yellow sweet clover is in full flower and some are ending their flowering. Alfalfa and white sweet clover are also beginning to flower out.
- Cutleaf teasel, Dipsacus laciniatus – Teasel is starting to bolt. Some that were low to the ground just last week, are now 3 to 4 ft. tall.
Northeast Illinois
- Bush honeysuckle, Lonicera spp. – Bush honeysuckle has just finished blooming last week.
- Dame's Rocket, Hesperis matronalis – Plants have been in bloom for about three weeks.
- Yellow flag, Iris pseudacorus – Plants have been in bloom for at least a week.
Northwest Illinois
- Yellow sweet clover, Melilotus officinalis –– Plants are beginning to flower but seed pods not completely formed yet. White Sweet Clover is not in flower yet but stands at mature height.
- Multiflora rose, Rosa multiflora– Established plants are beginning to flower. Leaves are fully expanded on newer recruitment.
- Garlic mustard, Alliaria petiolata – Plants have finished flowering and seed pods have fully developed. In drier spots leaves are beginning to senesce.
- Amur honeysuckle, Lonicera maackii – Plants are beginning to flower in dry uplands and are leaves have fully expanded in wetter areas.
Follow the Illinois Invasive Species Awareness blog for more phenology reports as well as other invasive species news! (Kelly Estes)
Author:
Kelly Estes