Invasive weeds pdf

If other equipment is brought in, or Glacier equipment is used outside of the park, it is pressure washed to prevent the transfer of seeds. Approaches to controlling invasive plants after a fire can range from aggressive removal of weeds followed by reintroduction of native species, to non-aggressive, natural revegetation. Glacier follows a strategy of noninterference whenever possible. If kept clear of invasive seeds, a recently burned area will regenerate on its own and native plants will re-establish.

Biologists and fire managers monitor areas where invasive plants were known to occur before a fire, or where it is suspected that seeds were introduced. If an infestation is discovered, weeds are removed by hand-pulling or with the use of herbicides, when appropriate. This management policy allows infestations to be treated individually, resulting in a minimally aggressive strategy. However, as fires become larger and more frequent, and invasive seeds are introduced further into the backcountry, aggressive measures may become the norm instead of the exception.

Prevention is arguably the most effective method of stopping the spread of invasive plants. At Glacier, prevention measures include prohibiting hay and requiring weed seed free pellets for livestock; mandatory inspections of boats for invasive aquatic plant and animal species; and a citizen science program which teaches visitors and staff to identify and report invasive weeds. The ecological degradation that invasive weeds cause can be avoided altogether by preventing seeds from being introduced into new areas and quickly suppressing infestations that do occur.

Explore This Park. If discovered in Virginia, these species need to be quickly mapped, photographed and reported to DCR. The primary management goal for early detection species is eradication, as preventing the establishment of newly arrived species will save valuable natural and economic resources. Department of Conservation and Recreation Conserve. Search DCR Site.

These changes in benefits could be collectively given values by respondents who indicate their WTP for such programs.

More recently, there had been attempts at undertaking bio-economic modelling to estimate changes to the values of natural areas. Bio-economic modelling involves modelling the physical changes to these areas and estimating the community values associated with the changes. For example, Hester et al. The work of Whitten and Bennett also used bio-economic modelling in determining the values of changing management strategies in the Murrambidgee River Flood Plain.

Higgins et al. CV was selected for its capacity to gather primary data rather than relying on benefit transfer methods of valuation. The data collected also has a tendency to be statistically significant.

A CV method has the advantage of conforming to given time and budget constraints. CV is one of the more established methodologies for goods that have non-market values. It is a survey-based technique used to elicit preferences for non-market goods Carson, ; Mitchell and Carson, ; Bishop and Romano, based on a particular or defined outcome Sinden and Thampapillai, By creating a pseudo-market, researchers are able to estimate individual preferences when it comes to non- market goods and services.

Other estimates of non-market values include value of forest quality protection Walsh, et al. Although used extensively in valuation of natural resource values, CV has its shortcomings such as its inability to identify and value actual impacts with certainty. The shortcomings of the CV method were discussed extensively in Carson , Clark, et al.

Since there is a wide range of understanding about the issue being evaluated, it was deemed important that respondents have a common basis of knowledge in order to elicit comparable estimates of WTP.

Realistic and identifiable scenarios were also chosen to elicit realistic answers. Counterfactual information was avoided, that is, the questions pertained to relevant future conditions for which a decision is required. In order to avoid biased responses, questions were framed to give a general perception of big business or the Government Hanneman, which would give the concept of balance and impartiality.

Questions were also constructed so that respondents could choose from a specified range of high and low prices and not feel pressured to identify either a high or low estimate, which may provide a biased answer Loomis, et al. A realistic and suitable payment vehicle was also chosen to allow respondents to provide realistic trade-off of utilities against monetary gain. Carson suggests that respondents should bid realistic values which could be enforced and collected, and to avoid protest bids from respondents.

Protest bids occur when the respondents bid so low or with zero bids in order to avoid paying additional taxes. These values are close to environmental levies currently charged in Queensland. Open-ended questions require the individual to identify their maximum WTP for a given situation. In sequential bidding respondents are asked to accept or reject a single specified sum with the question repeated using higher or lower bid values.

On the other hand, closed-ended questions are used to accept or reject a single specified sum or bid amount which can be varied across respondents. A smaller cognitive effort is used relative to open-ended questions Scarpa, et al. Close-ended questions have the added benefit of simulating the behaviour of the purchaser in an actual market place, such as whether or not to buy a particular good for a specified dollar amount.

Close-ended questions were used in this study. Due to resource and time constraints, the telephone survey method was used in the study. Telephone surveys ensure timeliness of response, increase response rate, and to ensure data consistency and were used to avoid the pitfalls of mail-out and other self-administered surveys Arrow, et al. Telephone surveys, however, are limited since visual aids cannot be used. An estimate of WTP was derived using each technique. Parametric analysis, as outlined in Gujarati involved specification and estimation of one or more probability models of individual choice.

Logit analysis was used as some of the questions in the survey were of a discrete nature. The analysis fits linear regression models for binary response data by the method of maximum likelihood which is carried out with the Fisher-scoring algorithm f-test Gujarati, Logistic regression, in this instance, is ordinary regression using the logit as the response variable see Appendix 4.

Two management scenarios were examined for two environmental weeds, Lantana and Singapore Daisy. One management scenario was stopping and preventing the current expansion of the environmental weed; the other was stopping weed expansion and reducing the area of infestation.

The sampling confidence indicates an estimate of the number of the total population that would have given the same answer if asked the same question. Table 1. A great majority considered environmental weeds problem at par with other environmental problems such as damage to the Great Barrier Reef, salinity, water quality and loss of production from weeds that affect agriculture Table 2.

Pre-survey knowledge of environmental weeds Table 2. Results and Discussions This study was an attempt to estimate the WTP of the Queensland population to support a program to control environmental weeds within areas of high conservation significance in the State.

Approximately Table 3. A similar trend occurs when the question asked related to another type of program, that is, reducing the area of spread Figures 6 and 7. The Logit analysis was used as it is the more conservative technique and as such, the results discussed in this section focus on the outcomes of the Logit technique. The outcomes for Singapore Daisy were not statistically different from the outcomes for Lantana.

Table 4. This could give an indication to policy makers that the current government expenditure is less than the socially optimal level or what the community is willing to pay for the control of exotic invasive species. This is interesting as AECgroup found that private landholders do not have sufficient financial or production incentive to invest in weed and pest animal management initiatives to the level required to provide the maximum benefit to society.

This may be due to the perceived higher costs associated with reducing the areas impacted by the weed. Goutweed PDF , Aegopodium podagraria , imported from Eurasia and frequently found in fields, thickets, woods and roadsides throughout PA. Garlic-mustard PDF , Alliaria petiolata , a weed of shady moist spots in suburban gardens, woods and floodplains throughout PA; introduced from Europe.

Wild chervil PDF , Anthriscus sylvestris , is a member of the carrot family that competes with native plants and carries a virus that can infect some vegetable crops. Narrowleaf bittercress PDF , C ar d amin e i m pat ien s , is a member of the mustard family native to Europe. Musk thistle PDF , Carduus nutans , is also known as nodding thistle from the way the flowers droop once mature. Greater celandine PDF , Chelidonium majus , is a four-petaled yellow flower from Europe that is poisonous.

Bull thistle PDF , Cirsium vulgare , is a large-flowered thistle with long spines and abundant seeds. Spiny Plumeless Thistle PDF , Carduus acanthoides , is a prickly, biennial plant that invades open areas and grasslands. Crown-vetch PDF , Coronilla varia , a sprawling perennial native to southern Europe planted extensively along highways. It spreads into open, grassland and prairie habitats. Jimsonweed PDF , Datura stramonium , is a state noxious weed that is highly toxic and frequently found in cultivated fields and other disturbed sites.

Goats rue PDF , Galega officinalis , is a state and federal noxious weed that is very poisonous to livestock. Orange day-lily PDF , Hemorocallis fulva , is a very hard perennial that grows in abundance along roadsides and old home sites. Giant hogweed PDF , Heracleum mantegazzianum , 15 feet tall member of the carrot family introduced from Eurasia. Its sap can cause blisters so it is listed as a federal and PA noxious weed. Dame's-rocket PDF , Hesperis matronalis , introduced from Europe to American gardens, now common in low woods floodplains and roadside ditches throughout PA.

Yellow flag iris PDF , Iris pseudacorus , is a showy ornamental plant commonly found in wetlands, along pond edges, and other wet areas where it can dominate. Purple loosestrife PDF , Lythrum salicaria , a European perennial with a woody base that has escaped gardens and destroyed large areas of waterfowl habitat by dominating wetlands and excluding all other plant life. Japanese pachysandra PDF , Pachysandra terminalis , is an evergreen perennial groundcover that can spread from cultivation into natural areas if left uncontrolled.

Beefsteak plant PDF , Perilla frutescens , a member of the mint family introduced from India now occasionally found in moist shaded roadsides and woods. Bristled knotweed PDF , Persicaria lon giseta , is an annual plant from Asia that can dominate wet, disturbed habitats.