Mark Leoschke - Academia.edu (original) (raw)

Papers by Mark Leoschke

Research paper thumbnail of Hybridization and Introgression in White and Yellow Ladyslipper Orchids (Cypripedium candidum and C. pubescens)

Journal of Heredity, Jul 1, 1991

ABSTRACT

Research paper thumbnail of Fire and the life history of shooting star, Dodecatheon meadia, in Iowa tallgrass prairie

Research paper thumbnail of Distribution of Iowa's Endangered and Threatened Vascular Plants

Research paper thumbnail of Review of 620 Wild Plants of North America: Fully Illustrated. By Tom Reaume

Research paper thumbnail of Review of \u3ci\u3e620 Wild Plants of North America: Fully Illustrated.\u3c/i\u3e By Tom Reaume

Beautifully and profusely illustrated with the author\u27s black-and-white drawings, the 12-year ... more Beautifully and profusely illustrated with the author\u27s black-and-white drawings, the 12-year project that became this book shows his love for plants. Tom Reaume focuses on a representative selection of primarily native vascular plants of the Great Plains of Canada and the northern United States found in forests, lakes, prairies, rivers, and wetlands. The book appears to be designed as a supplement for an introductory course in plant taxonomy. This book is a useful reference for those interested in the flora of the northern Great Plains and adjacent regions. I highly recommend it for college and university libraries where botany and biological illustration classes are taught on campus. The accurate, beautiful, and profuse illustrations are worth the price of the book by themselves

Research paper thumbnail of Precipitation contributes to plant height, but not reproductive effort, for western prairie fringed orchid ( Platanthera praeclara Sheviak Bowles): Evidence from herbarium records

Ecology and Evolution, 2020

The western fringed prairie orchid (WFPO) is a rare plant found in mesic to wet tallgrass prairie... more The western fringed prairie orchid (WFPO) is a rare plant found in mesic to wet tallgrass prairies in the Great Plains and Midwest regions of the United States. The size of WFPO populations varies considerably from year to year, and studies have suggested that population size is dependent on precipitation during critical periods in the plant's annual development. We hypothesized that plant height and reproductive effort would also be controlled by precipitation, either during these periods or over a broader period. We acquired available images of WFPO from 21 herbaria, and of these 141 individual plants had information adequate for analysis, although some population/year combinations were represented multiple times. For each specimen, we measured plant height (cm) and reproductive effort (as measured by total flower and bud count). We used bootstrapped linear regression, randomly selecting one individual from each population/year combination, to compare precipitation models, both during critical periods and the various summaries. We found that precipitation during the phenologically critical periods was a poor predictor of plant height and reproductive effort. Of the broader precipitation variables, accumulated precipitation from January 1 to collection date best described plant height. We also used correlations to detect a relationship among the variables WFPO height, reproductive effort, precipitation, latitude, and year of collection. Year of specimen collection was negatively correlated with WFPO plant height and accumulated precipitation, suggesting that both have declined in more recent years. Negative correlations with latitude also suggest height and precipitation decrease in the northern part of WFPO's range. Reproductive effort was not related to tested precipitation variables; however, it was weakly correlated with plant height. Although the results are limited, this study leverages available data and makes inferences on WFPO biology over broad ranges of time (1894-2012) and latitude (37.5°-49.9°).

Research paper thumbnail of Floristic Composition and Conservation Status of Fens in Iowa

The Journal of the Iowa Academy of Science: JIAS, 1992

Over 2~0 extant fens of varying condition were documented during an extensive inventory conducted... more Over 2~0 extant fens of varying condition were documented during an extensive inventory conducted in Iowa between 1986 and 1991. Approx1mat~ly half of the extant fens support endangered, threatened, special concern, or other rare plant species. Approximately 25 fens are outstandmg conservation pro~pects wit~ intact vegetation, high species richness, and rare species. Nearly 40% of all potential fen sites have been destroyed by cult1va~10n or dramage; another 30% remain unknown due to lack of a field visit, but most appear on aerial photographs to be very small, disturbed fragments. In addition to their traditionally recognized range in northwest Iowa, fens were found to !Jc: numerous and widespread in eastern Iowa. Most (95%) of the extant fens occurred on private lands; these were variously affected by grazmg (65%), cropfield edge effects (3 3%), potential expansion of woody plants (20%), drainage by tile lines or ditches (10%), excavation for ponds (2%), and mining of nearby sand and gravel deposits (2%). Over 225 species of vascular plants were identified on fens statewide during this inventory, of which 134 taxa occurred on at least five sites. Carex stricta was the most common graminoid among sites and was usually dominant within fens; other common species included Eupatorium maculatum, E. perfoliatum, Pycnanthemum virginianum, Aster umbellatus. A. punice11s, Helianthus grosseserratus, Asdepias incarnata, Lobelia siphilitica, Pedicularis lanceolata, and Helenium autttmnale. A large number of cosmopolitan species were shared between traditionally recognized fens in northwest Iowa and newly recognized fens (formerly called "hanging bogs") in eastern Iowa. Eastern fens are distinguished by the presence or greater prevalance of Che/one glabra. Heuchera richardsonii, Lythrum alatum, Onoclea sensibilis, Oxypolis rigidior, Salix candida, Saxifraga pensylvanica, Spiraea alba, Solidago riddellii, and Thelypteris palustris; western fens are distinguished by the presence or greater prevalance of Berula erecta, Lobelia kalmii, and Scirptts americanus. Zonation of vegetation is common in western fens, but uncommon in eastern fens.

Research paper thumbnail of Host, Larva, and Life History Notes for Macrophya nigra (Norton) (Hymenoptera: Tenthredinidae)

Proceedings of the Entomological Society of Washington

Research paper thumbnail of Hybridization and Introgression in White and Yellow Ladyslipper Orchids (Cypripedium candidum and C. pubescens)

Journal of Heredity, Jul 1, 1991

ABSTRACT

Research paper thumbnail of Fire and the life history of shooting star, Dodecatheon meadia, in Iowa tallgrass prairie

Research paper thumbnail of Distribution of Iowa's Endangered and Threatened Vascular Plants

Research paper thumbnail of Review of 620 Wild Plants of North America: Fully Illustrated. By Tom Reaume

Research paper thumbnail of Review of \u3ci\u3e620 Wild Plants of North America: Fully Illustrated.\u3c/i\u3e By Tom Reaume

Beautifully and profusely illustrated with the author\u27s black-and-white drawings, the 12-year ... more Beautifully and profusely illustrated with the author\u27s black-and-white drawings, the 12-year project that became this book shows his love for plants. Tom Reaume focuses on a representative selection of primarily native vascular plants of the Great Plains of Canada and the northern United States found in forests, lakes, prairies, rivers, and wetlands. The book appears to be designed as a supplement for an introductory course in plant taxonomy. This book is a useful reference for those interested in the flora of the northern Great Plains and adjacent regions. I highly recommend it for college and university libraries where botany and biological illustration classes are taught on campus. The accurate, beautiful, and profuse illustrations are worth the price of the book by themselves

Research paper thumbnail of Precipitation contributes to plant height, but not reproductive effort, for western prairie fringed orchid ( Platanthera praeclara Sheviak Bowles): Evidence from herbarium records

Ecology and Evolution, 2020

The western fringed prairie orchid (WFPO) is a rare plant found in mesic to wet tallgrass prairie... more The western fringed prairie orchid (WFPO) is a rare plant found in mesic to wet tallgrass prairies in the Great Plains and Midwest regions of the United States. The size of WFPO populations varies considerably from year to year, and studies have suggested that population size is dependent on precipitation during critical periods in the plant's annual development. We hypothesized that plant height and reproductive effort would also be controlled by precipitation, either during these periods or over a broader period. We acquired available images of WFPO from 21 herbaria, and of these 141 individual plants had information adequate for analysis, although some population/year combinations were represented multiple times. For each specimen, we measured plant height (cm) and reproductive effort (as measured by total flower and bud count). We used bootstrapped linear regression, randomly selecting one individual from each population/year combination, to compare precipitation models, both during critical periods and the various summaries. We found that precipitation during the phenologically critical periods was a poor predictor of plant height and reproductive effort. Of the broader precipitation variables, accumulated precipitation from January 1 to collection date best described plant height. We also used correlations to detect a relationship among the variables WFPO height, reproductive effort, precipitation, latitude, and year of collection. Year of specimen collection was negatively correlated with WFPO plant height and accumulated precipitation, suggesting that both have declined in more recent years. Negative correlations with latitude also suggest height and precipitation decrease in the northern part of WFPO's range. Reproductive effort was not related to tested precipitation variables; however, it was weakly correlated with plant height. Although the results are limited, this study leverages available data and makes inferences on WFPO biology over broad ranges of time (1894-2012) and latitude (37.5°-49.9°).

Research paper thumbnail of Floristic Composition and Conservation Status of Fens in Iowa

The Journal of the Iowa Academy of Science: JIAS, 1992

Over 2~0 extant fens of varying condition were documented during an extensive inventory conducted... more Over 2~0 extant fens of varying condition were documented during an extensive inventory conducted in Iowa between 1986 and 1991. Approx1mat~ly half of the extant fens support endangered, threatened, special concern, or other rare plant species. Approximately 25 fens are outstandmg conservation pro~pects wit~ intact vegetation, high species richness, and rare species. Nearly 40% of all potential fen sites have been destroyed by cult1va~10n or dramage; another 30% remain unknown due to lack of a field visit, but most appear on aerial photographs to be very small, disturbed fragments. In addition to their traditionally recognized range in northwest Iowa, fens were found to !Jc: numerous and widespread in eastern Iowa. Most (95%) of the extant fens occurred on private lands; these were variously affected by grazmg (65%), cropfield edge effects (3 3%), potential expansion of woody plants (20%), drainage by tile lines or ditches (10%), excavation for ponds (2%), and mining of nearby sand and gravel deposits (2%). Over 225 species of vascular plants were identified on fens statewide during this inventory, of which 134 taxa occurred on at least five sites. Carex stricta was the most common graminoid among sites and was usually dominant within fens; other common species included Eupatorium maculatum, E. perfoliatum, Pycnanthemum virginianum, Aster umbellatus. A. punice11s, Helianthus grosseserratus, Asdepias incarnata, Lobelia siphilitica, Pedicularis lanceolata, and Helenium autttmnale. A large number of cosmopolitan species were shared between traditionally recognized fens in northwest Iowa and newly recognized fens (formerly called "hanging bogs") in eastern Iowa. Eastern fens are distinguished by the presence or greater prevalance of Che/one glabra. Heuchera richardsonii, Lythrum alatum, Onoclea sensibilis, Oxypolis rigidior, Salix candida, Saxifraga pensylvanica, Spiraea alba, Solidago riddellii, and Thelypteris palustris; western fens are distinguished by the presence or greater prevalance of Berula erecta, Lobelia kalmii, and Scirptts americanus. Zonation of vegetation is common in western fens, but uncommon in eastern fens.

Research paper thumbnail of Host, Larva, and Life History Notes for Macrophya nigra (Norton) (Hymenoptera: Tenthredinidae)

Proceedings of the Entomological Society of Washington