Invasive earthworm and soil litter response to the experimental removal of white‐tailed deer and an invasive shrub

AbstractHen’s eyes (Ardisia crenata Sims) is a shade-tolerant invasive shrub displacing native understory in forests of the Coastal Plain of the southeastern United States. Few studies have explored herbicide effectiveness on A. crenata, with foliar applications of triclopyr amine or triclopyr ester typically referenced as the standard treatments. This study evaluated efficacy of eight foliar herbicide treatments and a nontreated check at three locations at 12 mo after the first treatment (12MAT1) and 12 mo after the second treatment (12MAT2) on established (greater than 8-cm high) and seedling (less than 8-cm high) A. crenata. Treatments were four triclopyr formulations: amine, ester, choline, and acid (all at 4.04 kg ae ha−1); imazamox (1.12 and 2.24 kg ae ha−1); flumioxazin (0.43 kg ai ha−1); and triclopyr amine plus flumioxazin (4.04 + 0.43 kg ae ha−1). At 12MAT1, triclopyr ester, the high rate of imazamox, and triclopyr acid resulted in greater control of established A. crenata than any other herbicide (68%, 66%, and 64%, respectively). At 12MAT2, all herbicides except flumioxazin resulted in some control of A. crenata. Triclopyr ester, triclopyr acid, and the high rate of imazamox provided 95%, 93%, and 92% control, respectively. Triclopyr choline did not perform as well as the acid or ester formulations, and the tank mix of flumioxazin and triclopyr amine did not improve control over triclopyr amine alone. This study identified triclopyr acid and imazamox (2.24 kg ae ha−1) as new options for A. crenata control and indicated variation in the performance among the four triclopyr formulations.

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The Experimental Removal of Preservative from Radiocarbon Samples

Plains Anthropologist ◽

10.1080/2052546.1968.11908501 ◽

1968 ◽

Vol 13 (40) ◽

pp. 146-147 ◽

Cited By ~ 2

Author(s):

George A. Agogino

Keyword(s):

Experimental Removal

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Biodiversity hanging by a thread: the importance of fungal litter-trapping systems in tropical rainforests

Biology Letters ◽

10.1098/rsbl.2011.1115 ◽

2011 ◽

Vol 8 (3) ◽

pp. 397-400 ◽

Cited By ~ 11

Author(s):

Jake L. Snaddon ◽

Edgar C. Turner ◽

Tom M. Fayle ◽

Chey V. Khen ◽

Paul Eggleton ◽

...

Keyword(s):

Species Richness ◽

Leaf Litter ◽

Plant Diversity ◽

Habitat Complexity ◽

Tropical Rainforests ◽

Dramatic Reduction ◽

Experimental Removal ◽

Crucial Component ◽

High Species Richness ◽

Vital Resource

The exceptionally high species richness of arthropods in tropical rainforests hinges on the complexity of the forest itself: that is, on features such as the high plant diversity, the layered nature of the canopy and the abundance and the diversity of epiphytes and litter. We here report on one important, but almost completely neglected, piece of this complex jigsaw—the intricate network of rhizomorph-forming fungi that ramify through the vegetation of the lower canopy and intercept falling leaf litter. We show that this litter-trapping network is abundant and intercepts substantial amounts of litter (257.3 kg ha −1 ): this exceeds the amount of material recorded in any other rainforest litter-trapping system. Experimental removal of this fungal network resulted in a dramatic reduction in both the abundance (decreased by 70.2 ± 4.1%) and morphospecies richness (decreased by 57.4 ± 5.1%) of arthropods. Since the lower canopy levels can contain the highest densities of arthropods, the proportion of the rainforest fauna dependent on the fungal networks is likely to be substantial. Fungal litter-trapping systems are therefore a crucial component of habitat complexity, providing a vital resource that contributes significantly to rainforest biodiversity.

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Impact of the experimental removal of lizards on Lyme disease risk

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2010.2402 ◽

2011 ◽

Vol 278 (1720) ◽

pp. 2970-2978 ◽

Cited By ~ 60

Author(s):

Andrea Swei ◽

Richard S. Ostfeld ◽

Robert S. Lane ◽

Cheryl J. Briggs

Keyword(s):

Lyme Disease ◽

Disease Ecology ◽

Disease Risk ◽

Large Fraction ◽

Host Community ◽

Deer Mice ◽

Infection Prevalence ◽

Alternate Host ◽

Experimental Removal ◽

Tick Infection

The distribution of vector meals in the host community is an important element of understanding and predicting vector-borne disease risk. Lizards (such as the western fence lizard; Sceloporus occidentalis ) play a unique role in Lyme disease ecology in the far-western United States. Lizards rather than mammals serve as the blood meal hosts for a large fraction of larval and nymphal western black-legged ticks ( Ixodes pacificus —the vector for Lyme disease in that region) but are not competent reservoirs for the pathogen, Borrelia burgdorferi . Prior studies have suggested that the net effect of lizards is to reduce risk of human exposure to Lyme disease, a hypothesis that we tested experimentally. Following experimental removal of lizards, we documented incomplete host switching by larval ticks (5.19%) from lizards to other hosts. Larval tick burdens increased on woodrats, a competent reservoir, but not on deer mice, a less competent pathogen reservoir. However, most larvae failed to find an alternate host. This resulted in significantly lower densities of nymphal ticks the following year. Unexpectedly, the removal of reservoir-incompetent lizards did not cause an increase in nymphal tick infection prevalence. The net result of lizard removal was a decrease in the density of infected nymphal ticks, and therefore a decreased risk to humans of Lyme disease. Our results indicate that an incompetent reservoir for a pathogen may, in fact, increase disease risk through the maintenance of higher vector density and therefore, higher density of infected vectors.

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