THE SCIENTIFIC RESEARCH PROGRAM

      Protocol for a study of peyote harvesting:

       Objective:

            To determine the effect of harvesting on survivorship of peyote under natural conditions in habitat in South Texas.


       Study site:

            The study will take place on a ranch in Jim Hogg or Webb County, Texas, where the harvesting of peyote is not permitted and where vigilance/patrolling and isolation by distance from the highway keep poaching to a minimum.


       Materials & Methods:

         Phase I:

            In the morning hours, working in beltline transects defined by steel stakes whose locations are recorded by high-resolution GPS, one hundred thirty (130) individually numbered plants with solitary stems (Group 1) will be harvested using the best traditional technique of cutting off the crown horizontally at ground level with a sharp tool such as a hand edger or putty knife. The position of each harvested plant will be determined and recorded by high-resolution GPS. As each plant is decapitated, the cut button will be measured (crown diameter and height), weighed to the nearest gram, inverted and left to dry approximately 15 cm north of the parent rootstock, at which point a durable aluminum tag bearing the plant's identification number will be attached to a 30-penny nail, which will be driven into the ground. At the end of the day, the cut crown of each plant will be planted to root about 30 cm north of the parent rootstock, except that 10 of the harvested crowns will be removed from the site for quantitative chemical analysis, to determine the average mescaline content of peyote plants not previously harvested.
            The measurements obtained on the cut crowns may yield data correlating survivorship with size of the plant at the time of harvest.
            In an adjacent beltline transect of similar size and likewise defined by GPS coordinates and steel stakes, one hundred (100) individually numbered plants with solitary stems (Group 2) will be similarly located with GPS coordinates, and the locations will be marked with 30-penny nails and aluminum identification tags placed 15 cm north of the plants. The treatment in this group will be to harvest the plants by cutting the subterranean stem (or possibly the root in smaller plants) about 2.5 cm below ground level, which is a common practice among peyote harvesters.
            Harvested tops of plants in Group 2 will be measured and weighed as in Group 1, and these crowns with 2.5 cm of subterranean stem (and possibly some root) will likewise be left inverted to dry during the day and will then be planted 30 cm north of the parent rootstock.
            In a third adjacent beltline transect of similar size, likewise defined by GPS coordinates and steel stakes, one hundred individually numbered negative control plants (Group 3) will be similarly located with GPS coordinates, and the locations will be marked with 30-penny nails and aluminum identification tags placed 15 cm north of the plants.
            These plants will not be harvested or otherwise disturbed, and will provide an estimate of the natural mortality rate in the population over the period of the study.

            Approximately six months after the harvesting treatment of Groups 1 and 2, the study site will be visited again, and the location of each plant in all three groups will be examined. Each plant from Groups 1 and 2 will be scored either positive for regrowth of new stem tissue visible above ground level, or negative for such regrowth, and the percentages of plants in Groups 1 and 2 that showed regrowth will be noted by inspection. Regrowth will be further characterized by noting the number and diameter of new crowns produced by each plant showing regrowth.
            Plants in Group 3 will be located and scored either as alive or dead.
            The crowns of replanted tops of plants harvested at the beginning of the study (Groups 1 and 2) will also be measured, and the mean crown diameter for the each group of harvested plants will be compared to the mean crown diameter of unharvested plants in Group 3.

          Addendum 12-2008: Due respectively to access limitations and respect for the concerns of the landowner we modified the above to a harvest and tagging of 50 individuals with a monitored and containerized replanting of the cut buttons.
          Initial data generated after months 8 & 12 of this study]
          Addendum March 2012: The results after 48 months are now available.


            Approximately 12 months after the harvesting treatments were applied to Groups 1 and 2, the study site will be visited for the third time, and the location of each plant will be examined. Each plant from Groups 1 and 2 will be scored either positive for regrowth of new stem tissue visible above ground level, or negative for such regrowth, and the percentages of plants in Groups 1 and 2 that showed regrowth will be noted by inspection. Plants in Group 3 will be located and scored as either alive or dead. At the 12-month time point from the beginning of the study, it will be assumed likely that any plants not yet showing regrowth are dead.
            From these results we will observe the normal annual mortality rate in Group 3, and any excess mortality observed in Group 1 or Group 2, compared to that in Group 3, will be attributed to damage associated with harvesting.


         Phase II:

            At 24 months after the beginning of the study, all plants in which regrowth was not observed up to the 12-month time point, will be rechecked for any late regrowth. The rootstocks of such plants will be dug up at this point (if they can be found) and examined for signs of life.
            At this time, Phase II of the study will begin.
            At this point the surviving plants in Group 1 will be divided into two subgroups, 1A and 1B, such that the number of individual plants in 1A is equal to the number of individual plants in 1B plus 20.
        The Phase II treatment in Groups 1A and 2 will consist of harvesting all new crowns produced by regrowth of the rootstocks of plants harvested at the beginning of Phase I. All harvesting in Phase II will be done using best traditional technique, and all regrowth buttons will be harvested from each plant, as is common commercial practice in South Texas.
            Measurements of harvested crown diameter, height and weight will be taken as in Phase I.
            The harvested regrowth buttons will likewise be replanted, ca. 15 cm south of the parent rootstock.
            Group 1B will not be reharvested, but will be left as a once-harvested group for comparison to the twice-harvested groups 1A and 2 and to the never-harvested Group 3.
            Ten of the regrowth buttons harvested from ten different individual plants in the twice-harvested Group 1A at this time will be removed from the site for quantitative analysis of mescaline content.

            The twice-harvested parent plants will be checked for regrowth at 6, 12 and 24 months after the second harvest (i.e., at 30, 36 and 48 months from the initial harvest at the beginning of Phase I of the study).
            The same measurements and data will be recorded in Phase II as in Phase I.
            This second phase of the study is designed to determine the percentage of plants that can withstand two successive harvestings at a two-year interval (which often happens in practice) and produce a second round of regrowth of new stems.

            At the 48-month time point from the beginning of the study, 10 regrowth buttons will be harvested from 10 different individual plants in Group 1A and removed from the site for quantitative analysis of mescaline content. The reason underlying the analysis of multiple plants rather than just one is to help us learn an average value and lessen the influence of the well known potential variability in alkaloid content between individual plants.
            That will allow comparison of mescaline content of buttons from never-previously-harvested, once-harvested and twice-harvested plants. Mescaline concentration will be expressed on dry-weight basis as mg of mescaline per gram of desiccated stem tissue.


       Intended purpose of this proposed study:

            Our hopes are to collect a variety of data points in this multipronged study that are capable of assessing the impact of conscientious harvesting on plant survival or mortality rates, growth rates of post-harvest regrowth and alkaloid content. It is also designed to assess the same parameters for plants harvested twice and to permit comparisons with well matched unharvested control plants.
            It will also furnish data that will enable a direct assessment of what is presently indicated by study to be the best technique of sustainably harvesting peyote.
            This study has a tangential benefit of enabling an assessment of the success rate of direct planting of unrooted cuttings of varying sizes and a look at their rates of growth during the duration of the study period.





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