User:Mistoe

Desert mistletoe Phoradendron californicum are parasitic plants that are found on many different shrubs or trees across the Sonoran Desert (Dimmitt 2006).Desert mistletoe are found in foothills and desert areas under 4,000 feet elevation (Dimmitt 2006). They can be found in the desert of Southern Nevada and Southern California to Central Baja California and Southern Sonoran Desert (Dimmitt 2006). They are leafless plants that hang from their host trees. Also, during the winter the mistletoe species produce flowers that are inconspicuous but very fragrant. Desert mistletoe is frequently found on legumous woody desert trees (Spurrier & Smith 2006).Desert mistletoe belongs to the Vicaceae (loranthaleak) mistletoe family (Dimmitt 2006). Phoradendron californicum is most commonly found on Palo Verde (Cercidium) and Mesquite (Prosopis) (Spurrier & Smith 2006). In order to survive, desert mistletoe takes water and nutrients from their host plants making them a parasitic species (Spurrier & Smith 2006, Dimmitt 2006). However, they are also considered plants because they photosynthesize (Spurrier & Smith 2006). Approximately 1,000 mistletoe species are identified (Dimmitt 2006).

This species has a unique reproductive strategy. Female desert mistletoe produces fragrant, red berries that are eaten by a type of bird that inhabits much of the Sonoran Desert, the Phainopepla Phainopepla nitens (Dimmitt 2006). Phainopeplas cannot digest the seed of desert mistletoe, so the birds disperse the seeds when they defecate or wipes its bill on the trees (Dimmitt 2006). The seeds then grow into desert mistletoe. Our project and research is focused on this interesting plant and parasite in order to gain better knowledge of this unusual organism. The research conducted focused on finding desert mistletoe and the plants that the mistletoe primarily inhabits; and in this case, Palo Verde trees and Mesquite trees are its chosen hosts.

Kingdom: Plantae Phylum:  Magnoliopsida Class:   Magnoliopsida Order:   Sentalales Family:  Viscaceae Genus:   Phoradendron Species: Phoradendron californicum Common name: desert mistletoe

Here is the information on are research of desert mistletoe Phoradendron californicum:

Materials One notebook for notes One notebook for record keeping Pens Measuring Tape Camera Epple, Anne. A Field Guide to the Plants of Arizona. Arizona: Lewann Publishing Company, 1995. Bowers, Janice and Brian Wignall. Shrubs and Trees of the Southwest Deserts. Arizona: Western National Parks Association, 1993. “Viscaceae (Loranthaceae)” Arizona-Sonora: Desert Museum. Desert Museum Online, 2009. Web. 5 Oct. 2009. . “Desert Mistletoe” Web of Science, 2009. Web. 5 Oct. 2009. .

Methods As a group, we drove out to Greasewood Park on October 5, 2009 around 5:00 p.m. in the evening. For two hours, we collected data until the sun went down, around 7:00 p.m. We collected information for one transect. We planned to go to 3 different areas in Tucson, Arizona to collect information: Greasewood Park, Foothills area, and Urban development. We would do 6 transects at each location. Each transect would be collecting data in a straight line for 30 meters. 3 transects were collected randomly in the area on a drier pathway, while 3 of the other transects were collected near a wash. For each transect, we recorded the plants that were in our pathway. We kept track of the numbers of each plant, and which plants that had desert mistletoe living on them, and the plants that did not. For some plants that we did not know, we identified with the plant books (see the Materials section). The foothills area was done on October 14, 2009 from 7:30 a.m. until 8:30 a.m. More specifically, the Foothills area used for this experiment was on River Road and Shannon Road. The same methods were done for the 6 transects. However, only one transect was completed on October 14, 2009. The other transects were completed on October 18, 2009 from 11:00 a.m. until about 3:00 p.m. The urban development was studied on October 22, 2009 from 4:00 p.m. until 6:00 p.m.  The urban development area was near the University of Arizona, on Vine Street. The data that was collected was interpreted into graphs and tables.

Results

Figure 1 This chart illustrates Mesquite trees for Urban versus Greasewood Park. It shows that there are no infected trees in the urban area and the proportion of infected and uninfected Mesquite trees in Greasewood Park.

Figure 2 This chart shows that there are no Palo Verde trees infected at the urban area and also shows the Palo Verde tree proportion of infected and uninfected trees for Greasewood Park.

Figure 3 This chart shows the infection of Palo Verde and Mesquite trees versus the Uninfected trees for the Foothills area. Figure 4 This chart shows the overall infection of the trees for each site. 1 is the urban development. 2 is the Greasewood Park. 3 is the Foothills area.

Discussion In our research we explored the desert mistletoe, (Phoradendron californicum, Viscaceae) in different areas of Tucson, Arizona. We explored desert mistletoe in an urban area, the Foothills area (north), and a more South area Greasewood Park. We found that in an urban development, we found no desert mistletoe on the trees. There was no growth or even evidence on the mesquite and Palo Verde trees (refer to the Results section). There can be a few explanations for this: first, in urban developments, plants are treated more and taken care of more so that this parasite will not grow onto these trees or will be removed. Most of the trees were found on residence's yard. Another explanation for the lack of desert mistletoe in the urban development would be that the bird responsible for most of the dispersal, Phainopepla (Phainopepla nitens) would not be found in the urban development. We also discovered that there were more infected plants in Greasewood Park compared to the Foothills area. By looking at the graphs under the results section, it is clear that Mesquite trees as well as Palo Verde trees are more infected at Greasewood Park than the Foothills area. This may be due to the fact that Greasewood Park is a more “wet” area. For example, the park contains a much larger wash area than the Foothills area. This may be a more suitable for the Phainopepla to survive, and thus disperse more desert mistletoe. Another reason would be that the trees with more access to water would be more plentiful in nutrients, and thus can help the parasite grow more, and thus have more berries for the Phainopepla. Upon our research, we also noticed that the Foothills area had much more residence surrounding than Greasewood Park. This may affect the desert mistletoe dispersal since the Phainopepla would be more discrete in areas with more human activity. Also, the Foothills area is more North than the other areas and had a very little wash area compared to Greasewood Park. Much of the plants we saw with desert mistletoe, (Phoradendron californicum, Viscaceae) was mostly trees. We did not see any bushes (creosote, ambrosia, acacia) with the parasite. We noticed that Mesquite and Palo Verde trees had the most infection. Between the Mesquite and Palo Verde trees that infection was 76% and 75% respectively. Prior to conducting our research, we believed that desert mistletoe would prefer Mesquite trees, however, by looking at our results it shows there is not a strong preference. Much more research can be expanded on this topic. For instance, much more different areas may be explored, perhaps outside of Tucson, Arizona. The more data that is collected will tell us more about this parasite. Also, if this research was continued, it would be interesting to see how many patches of desert mistletoe would grow depending on type of tree as well as size of tree. If this research was continued, we might have conducted some areas differently. For instance, we may explore in some areas that are more “wild.” Also, we may expand the transects to get more data. We realized by collecting more data, our results would be interesting to see different correlations. Nonetheless, our results did prove differently than our original hypothesis.

Works Cited Bowers, Janice and Brian Wignall. Shrubs and Trees of the Southwest Deserts. Arizona: Western National Parks Association, 1993. “Desert Mistletoe” Web of Science, 2009. Web. 5 Oct. 2009. . Epple, Anne. A Field Guide to the Plants of Arizona. Arizona: Lewann Publishing Company, 1995. “Viscaceae (Loranthaceae)” Arizona-Sonora: Desert Museum. Desert Museum Online, 2009. Web. 5 Oct. 2009. .