Background

We present a detailed history of the PFP elsewhere (Bocinsky and Varien 2017; Ermigiotti et al. 2020; Varien et al. 2018), and the reader should consult those sources for an account of how the experimental farming program developed and the individuals who contributed to the project. Here, we summarize details of the project to provide a background for this chapter.

The idea for the PFP emerged from a 2004 Native American Graves Protection and Repatriation Act (NAGPRA) consultation with Crow Canyon, the HCPO, and the National Park Service to discuss the Goodman Point Archaeological Project. At the end of the meeting, Crow Canyon researchers asked whether there were other studies HCPO would like Crow Canyon to conduct; they requested that Crow Canyon research ancestral Pueblo maize farming and link that to modern Pueblo farming. Their request led the HCPO and Crow Canyon to codesign the PFP, along with input from other eastern Pueblo farmers and researchers who study Pueblo maize agriculture. In 2005, Crow Canyon hosted a meeting of Pueblo farmers, scholars, and HCPO staff. The farmers came from Hopi, Jemez, Ohkay Owingeh, and Tesuque/Zuni Pueblos, and they recommended we initiate an experimental farming program focused on direct-precipitation maize farming (also known as dryland farming). They also agreed the Hopi farmers should lead the project since they continue to use direct-precipitation maize farming today.

Hopi farmers returned to Crow Canyon’s campus in 2007 to select the locations for the gardens. We began with five gardens on campus but eventually abandoned two of those plots due to modern site disturbance and poor yields. In 2015, we added a mesa top garden on farmland about 50 km (31 miles) north of Crow Canyon near Dove Creek, Colorado (figure 4.1).

Farmers from the HCPO and several members from the Cultural Resources Advisory Task Team (CRATT) visited CCAC each year between 2008 and 2017. They instructed Crow Canyon staff on how to plant, gave advice on tending plants throughout the growing season, and returned to supervise the harvest. Crow Canyon staff and volunteers have continued to plant and harvest the gardens from 2018 to the present. The Hopi farmers provided seed for the initial 2008 planting. Several different varieties of corn seed (poshumi) were planted between 2008 and 2010. Since 2011 only Hopi blue (sakwapqà ö) and white corn (qotsaqá ö) have been planted, using seed from previous harvests. During each growing season, CCAC staff made weekly visits to the gardens to measure maize vegetative and reproductive growth. They also recorded environmental data and documented yields for each harvest. During the PFP, Hopi farmers shared their perspectives on maize farming and corn culture. These insights shaped our understanding of how the ancestral Pueblo people may have similarly been sustained, physically and spiritually, by maize.

Hopi Knowledge

The HPCO staff and farmers who participated in in the PFP stated that one of their primary objectives was learning whether Hopi seed and farming practices would succeed in the central Mesa Verde region. Some clans view this area as a part of their traditional homeland (see Kuwanwisiwma and Bernardini, chapter 5 in this volume). Leigh Kuwanwisiwma notes, this connection remains important to Hopi people. “A corn culture that we see today in Hopi is shaped by a corn culture from a millennium ago.” Stewart Koyiyumptewa states that the values of the “corn culture” pervade every aspect of Hopi life. “From when we enter the world to our end life, all of that is involved using corn. They are the primary source for our prayer offerings.”

Throughout the PFP, Hopi farmers shared their knowledge about the fundamental importance of maize and maize farming to Hopi people and Hopi culture. Without exception, each emphasized that success goes far beyond the technical details of planting, tending, and harvesting. “Agriculture is an act of faith for the Hopi that serves as a religious focus as well as an economic activity. The themes of humility, cooperation, respect and universal earth stewardship became the way of life for all Hopis” (Kuwanwisiwma 2005, 15–16). This viewpoint enhanced the understanding of Pueblo farming for the non-Hopi members of our team, and, where appropriate, we include their knowledge and perspectives in the outreach and educational materials advanced by the PFP.

All crops, especially maize, necessitate nurturing. “They are your children,” our advisors repeatedly informed us. “They need encouragement, sing to them each time you approach.”

The phrases for each stage of development of the maize plants, loosely translated, are equivalent to terms used for the stages of a human development, for example, crawling, standing upright, sexual maturity (Ermigiotti et al. 2020). This kinship with corn, along with the belief that a (Hopi) farmer needs to have a good heart and prayers, represents the most important factor leading to a good harvest and agricultural sustainability.

One point of contrast between the Hopi farmers who worked on the PFP and the Western scientific researchers was that the Hopi never look at the crops as statistics or data. In our efforts to collect data and to accurately quantify yields, Hopi advisors felt that we were reluctant to step further into the process and fully understand corn farming because we were not eating some of the fresh corn, sami, at the milky kernel stage. They pointed out that this may affect yields because when corn is not used for the purpose it was intended, it pouts and will not grow to its full potential. Stewart Koyiyumptewa uses the word motsiwngwa to refer to a time to indulge in the fruits of one’s labor ensuring future success. We hope to better address this concern. Over the duration of the PFP the Hopi participants have come to accept our need to document and record all aspects of the process throughout the project.

Experimental Maize Farming and the Pueblo Farming Project

Ethnographic observations and scientific interests in Indigenous farming practices date to the late nineteenth and early twentieth centuries (e.g., Beaglehole 1937; Clark 1928; Cushing [1974] 1920; Forde 1931; Hack 1942; Whiting 1966). Researchers rely on experimental gardening to supplement our understanding of pre-Hispanic agricultural practices (Bellorado 2007). Experimental maize farming at Mesa Verde National Park, conducted from 1918 to 1936, began as a demonstration garden to facilitate public education (Franke and Watson 1936). Navajo Park Service employees planted this garden using traditional deep-planting and wide-spacing methods. The longevity of this program demonstrated the sustainability of ancient garden plots in climatic conditions not unlike those today.

Their repeated planting of maize in the same garden addressed questions surrounding soil depletion. Experimenters learned that soil fertility is maintained through the wide-spacing of plants and by interspacing the plants to different locations within the garden each year. Additionally, the project addressed the importance of winter precipitation in maintaining adequate soil moisture for the successful germination of seeds and the subsequent growing season (Franke and Watson 1936).

In 1975, The Southwestern Archaeological Program at San José State University established five experimental gardens at Hovenweep National Monument (Hammett and Hornbeck 1984; Litzinger 1976; Winter 1976). Each garden tested a different variable to investigate agricultural production. Two plots compared water control devices: one a check dam and the other canyon bottom terraces. A third garden, located on the mesa top, determined the effects of supplemental watering on growth. A fourth garden, previously set up for food production, used a variety of cultivated plants to establish their potential under current climatic conditions. A fifth garden, established near Pleasant View, Colorado, was not weeded to assess competition from invasive plant species. The experimental gardens yielded poor harvests but demonstrated that successful gardens need adequate soil depth to maintain moisture, protection from herbivores, and reduced-or-no competition from weeds (Litzinger 1976).

In 1979 and 1980, Dolores Archaeological Program (DAP) researchers planted two large experimental farming gardens using twelve varieties of southwestern maize and an assortment of beans and squash species to document variation in growth rates and productivity. They noted that maize development and yield were affected by plant spacing and density. The gardens were affected by topography, and cold air drainage increased the possibility of crop failure (Bellorado 2007; Bye and Shuster 1984; Shuster 1981, 1983).

Karen Adams, Deborah Muenchrath, and Dylan Schwindt (1999) examined the morphology, phenology, and physiology of a Southwest US maize cultivar in a two-year (1992, 1993) controlled garden experiment. Their analysis of the yields helped refine methods used to interpret archaeological maize remains (Bellorado 2007). Adams and others (2006) conducted another two-year (2004, 2005) experimental farming project, Maize of American Indigenous Societies (MAÍS), a grow-out of 123 maize accessions curated by the USDA. The USDA originally collected most of these accessions from American Indian farmers in the mid-1900s. The MAÍS project crops were irrigated to provide optimal growing conditions. These data helped define distinctive morphological groups and field traits within the accessions (Adams et al. 2006; Bellorado 2007).

In 2003 and 2004 the Animas–La Plata Archaeological Project (ALP) supported a program to assess connections between settlement locations and farming catchments. Benjamin Bellorado (2007, 2009) created several experimental gardens. Using traditional direct precipitation agricultural methods, including deep-planting and wide-spacing (Dominguez and Kolm 2005), several different Indigenous maize varieties were grown to assess variability in yields. Hand pollination maintained the genetic distinctness of the maize varieties. Weather station and a temperature monitor transects recorded the length of the frost-free growing season and the effects of cold-air drainage. These experiments demonstrated that simple water management practices, combined with an adequate frost-free growing season, and the accumulation of sufficient growing season heat units, or Growing Degree Days (GDDs), resulted in sustainable maize yields (Bellorado 2007, 2009).

These projects largely laid the foundation for Crow Canyon’s Pueblo Farming Project. Bellorado helped set up the research design for the PFP using methodology incorporated by the ALP studies. Record keeping of temperature, precipitation, soil moisture, weekly vegetative, and reproductive growth stages; monitoring the effects of cold air drainage on the length of the growing season; and the assessment of yields helped create a long-term dataset for the PFP that can now provide a valuable baseline for future studies (Bellorado 2007, 2009; Bocinsky and Varien 2017; Ermigiotti et al. 2020).

Comparing Crow Canyon Campus Gardens to the Dove Creek Garden

Pueblo settlement during most of the AD 600 to 1280 period occurred predominantly in mesa top settings (Glowacki et al., chapter 12 in this volume). Deep aeolian soil, called Mesa Verde loess, covers these mesa tops. Researchers believe ancestral Pueblo farmers focused on these rich soils for maize agriculture (Van West 1994), just as modern farming occurs on these soils.

In 2015, Mike Coffey, a local farmer from Dove Creek, Colorado, provided us with a space on his land that he thought would be ideal for maize. We call this plot the “Mike Coffey Garden” (MCG) and have farmed it from 2015 to the present. Next, we compare the environmental and ecological characteristics of the MCG plot with three plots on Crow Canyon’s campus: Paul’s Old Garden (POG), the Pueblo Learning Center Garden (PLC), and the Check Dam Garden (CDG).

Setting: Landform, Elevation, and Aspect

The settings of the gardens discussed here vary in several important ways. Those located on the Crow Canyon campus—the POG, PLC, and CDG—are a maximum of 153 m apart across an area of about 12,300 m². All these gardens lie between 6,120 and 6,140 ft. in elevation. The gardens are located along the east-central part of Crow Canyon, a south-flowing tributary to McElmo Canyon, and have either flat or west-southwest exposures. The POG is located on level ground near the bottom of Crow Canyon, and both the PLC and CDG are situated in small, westerly flowing drainages on the east side of Crow Canyon, about 4 to 6 m above the POG. Due to their location in small drainages, the PLC and CDG capture runoff events while the POG typically does not. Although the elevations of gardens vary slightly, their location within the canyon has increased impacts from cold air drainage that shortened the growing season in some years (Ermigiotti et al. 2020).

In contrast, the MCG garden lies at a higher elevation, about 50 km northwest of the Crow Canyon campus in an upland setting east of Dove Creek, Colorado. Located along the southern flank of a small, southwestern-flowing drainage, the garden sits at an elevation of about 7,300 ft. This elevation typically results in larger winter snow accumulations compared to the campus gardens, and the topography immediately around this field allows cold air to drain away from the field into major nearby canyons (Gillreath-Brown et al. 2019). The northern aspect of the field helps retain soil moisture from reduced sun and wind exposure. Unlike other fields discussed here, the MCG is situated within an existing agricultural field in which beans and wheat have been grown in rotation for at least the past forty years.

Soils

All gardens located on the Crow Canyon campus are situated on soils classified by The Natural Resources Conservation Service (NRCS) as Wetherill loam with 3–6 percent slopes. The POG is also partially located on Ackmen Loam with 1–3 percent slopes (Soil Survey Geographic Database [Soil Survey Staff 2020]). Despite general similarities, significant variation exists in the soils present in the gardens (Fadem and Diederichs 2019). For instance, soils in the PLC garden are sandier given its location in an ephemeral, narrow drainage where eroding upslope sediments are deposited, whereas the composition of the POG soils suggests the presence of more clay and less aggradation of colluvial sediments (Utah State University Analytical Laboratories 2009). Slight differences, like those above, influence infiltration rates and water-holding capacity, and the topographic locations of the fields also impacts their ability to capture runoff events. All these factors influence the amount of moisture that gets on, and remains in, the gardens.

The NRCS designated soils present in the MCG as Illex-Granath complex with 6 to 12 percent slopes (Soil Survey Staff 2020). These soils are a clay loam with good infiltration and water retention properties. This field has the deepest soil of any field discussed here, and it has darker sediment; this is likely an indication of remnant organic material possibly from a stand of Gambel oak (Quercus gambelii) that was cleared, burned, or removed when the field was created in the early 1900s. The small drainage just to the north of the field is also one of the wettest areas in the surrounding landscape during the spring, suggesting the presence of a perched water table or some other subsurface water.

Growing Season: Temperature and Moisture

There is no debate that water and temperature are two of the greatest environmental factors influencing maize development and yields (Adams et al. 2006; Benson 2010, 2011; Muenchrath and Salvador 1995). Precipitation delivered as rain or snow is stored in the soil. Soil moisture can be increased by water run-on, diversion, or irrigation, or by capturing water and soil using check dams.

Precipitation in the Mesa Verde region comes mainly as winter snow (December to March) and summer (July to September) monsoonal rains. Average annual precipitation varies widely across the landscape and is affected by elevation and proximity to local landforms (Benson 2010; Van West and Dean 2000). The National Corn Handbook, Purdue University Cooperative Extension Service, states, “with dryland farming, corn is generally not grown in areas receiving less than 25 inches (60 cm) of annual precipitation” (Neild and Newman n.d.). Suggested lower threshold requirements for Southwest maize productivity are 11.8 inches (30 cm) of precipitation and 1,800 GDD (Benson 2011; Shaw 1988). The annual precipitation for the PFP study area averaged 12 inches (30.48 cm) of precipitation during a twelve-year period (2008–2019), which is close to the thirty-year (1981–2010) average for nearby Cortez, Colorado (J. Andrus, NOAA, NWS Cooperative weather observer, personal communication, November 2021). The timing of precipitation and the availability of soil moisture are as important as total annual precipitation (Adams et al. 1999; Van West and Dean 2000). The plant’s access to nutrients also depends on sufficient soil moisture, since nutrients in the soil are available to the plant in solution and cannot be absorbed without it. Inadequate soil moisture may result in nutrient deficiencies (Muenchrath and Salvador 1995).

Soil moisture and air temperatures influence both vegetative growth and reproductive development. Stress during stages of development can reduce yields, impacting seedling emergence, anthesis (tasseling), and silking (Adams et al. 1999; Adams et al. 2006).

The length of the growing season for maize is more nuanced than the number of frost-free days in any given location or year. In the spring, maize can survive a frost of about 28°F (−2°C) because the growing point (apical meristem) of the plant remains below the ground surface. Some southwestern landraces can emerge from deeper planting depths, up to 40 cm, due to the development of a significantly elongated mesocotyl. This adaptation allows for earlier planting while insulating the growing point of the plant (Adams et al. 2006; Bousselot et al. 2017; Collins 1914; Muenchrath and Salvador 1995; Troyer 1997).

Plant development and kernel maturity depend on accumulated heat units or cumulative GDDs, which are not the same as solar days. The ideal temperature for maize growth is between 50°F and 86°F (10 to 30°C). Beyond these thresholds, maize growth and development are limited. The accumulation of GDDs is calculated based on these thresholds.1 Many modern hybrids require an average of 2,400 to 3,200 GDD (Adams et al. 2006). Growing season may be influenced by environmental adaptations of the cultivar. Bellorado’s (2007, 2009) experimental studies in Ridges Basin have demonstrated—and PFP results confirm (Ermigiotti et al. 2020)—that the GDD requirements for some Indigenous maize varieties to produce yields are far below the above range (table 4.1). Further, variation in the length of the frost-free season is not always directly correlated to elevation but is dramatically influenced by cold air drainage (Adams 1979; Bellorado 2007).

Table 4.1. Environmental data and yields for the PFP Gardens.

Source: Table by authors.

Soil Moisture and Yields

A water year (WY) refers to the amount of precipitation that occurs from October 1 to September 30 of the following year. The WY year is used to account for moisture that accumulates in the soil after harvest but before the start of the calendar year. Precipitation that falls during the growing season is critical for maize growth and maturation. Table 4.1 illustrates the Daymet (Thornton et al. 2020) environmental data for the gardens and suggests the MCG received more cumulative moisture during the water year than the PLC, POG, or CDG. Although some individual summer storms did provide more moisture to the campus gardens than to the MCG, the MCG received more moisture during the growing season, allowing for more moisture to enter the soil column when the maize was growing and maturing. In some years, such as 2015, the precipitation difference was especially pronounced, and the difference resulted in higher yields for the MCG compared to campus gardens.

Precipitation that falls after the previous harvest, and prior to the next planting, influences overall soil moisture and yields. This precipitation provides soil moisture for seed germination and early-stage growth until summer monsoons arrive. The importance of this moisture can be seen in 2018 data. In that year, both the MCG and campus gardens received similar (and scant) overall precipitation during the growing season, with only about 5 mm of precipitation separating the two garden locations (table 4.1). In terms of the entire WY however, the MCG received 27 mm more precipitation, and most of that fell prior to planting outside of the growing season. Yields from the MCG outperformed any of the campus gardens, which produced little-to-no yields. Greater winter moisture accumulations in the upland garden area, though not the only factor influencing greater yields at the MCG in 2018, allowed for better conditions at the time of planting and through the early growing season.

Differences in soil composition between the MCG and campus gardens influence how they absorb and retain available moisture. The MCG soils have more clay at every level of the rooting column, grading from clay loam at shallower depths to clay at around 37 to 60 inches of depth. Due to the high clay content, water permeability is slow, but these sediments hold more moisture in the root zone allowing for increased maize production (Benson 2011; Dominguez and Kolm 2005).

Soils in the campus gardens possess less clay and are classified as loams with slightly better water permeability. More site-specific analysis of sediments in the POG, PLC, and CDG also suggest that although there are broad similarities in attributes, subtle—but important—differences are also present in the campus gardens. For instance, the sandier soils in the PLC allow for increased water permeability; however, these soils retain less moisture than the POG, which has higher clay content and potentially deeper sediments (Fadem and Diederichs 2019).

The importance of overall precipitation and soil characteristics is reflected in the cumulative soil moisture data shown in figure 4.3. Beginning in 2015, and in partnership with the University of North Texas, and specifically Dr. Steve Wolverton and Dr. Lisa Nagaoka, soil temperature and moisture sensors were placed in three of the PFP gardens (CDG, PLC, and MCG) and have comparable data through 2019. A moisture monitor was also added to the POG in 2020. Sensors were deployed at three depths: 15 cm, 30 cm, and 45 cm below the modern ground surface. We used Decagon Devices 5TM soil temperature and moisture sensors in tandem with Em50 series data loggers to collect data. These sensors recorded the temperature (°C) and the amount of water vapor (expressed in m³ of vapor water content per m³ of soil) every hour over the course of their deployment. These data are depicted in figure 4.3, with the teal line representing the MCG at each depth, the solid red line representing the average of the campus gardens at each depth, and the light red bars indicating the high and low values across the campus gardens.

The primary difference between the MCG and the campus is the stable and relatively high level of moisture retained at 45 cm at the MCG. The values for the 15 cm and 30 cm depths are broadly similar across all gardens, although they do fluctuate in response to specific storms or precipitation events. At 45 cm of depth, the MCG retains much more moisture, and that level is remarkably stable throughout the year compared to the other gardens. This is at least partly a function of more precipitation at the MCG, the higher clay content of the soils, and the depth of soils in the field.

In addition to precipitation and soil characteristics, differences in ambient temperature between the MCG and the campus gardens affect the amount of soil moisture present, which, in turn, influences the rate of evapotranspiration in the plants. The previous section on GDDs suggests that temperatures are slightly cooler at the MCG compared to the campus gardens. Maximum growth rates for maize occur at about 30°C (86°F), higher temperatures increase soil evaporation, reduce stored moisture, and cause the plant to wilt. Finally, the northern aspect of the MCG also reduces exposure to wind and solar radiation, further helping to retain soil moisture.

Discussion

Determining whether Hopi seed and Hopi farming practices would succeed in the central Mesa Verde region represents an important goal of the PFP and something especially meaningful for the Hopi members of the team. Our experimental farming project demonstrates that Hopi seed and farming techniques indeed do produce yields, and in the case of the MCG garden exceptionally abundant yields. A heuristic example illustrates just how exceptional. Ethnographic accounts estimate a desirable goal of producing 160 kg of maize per person per year (Adams et al. 2006, 52; Van West 1994, 125), or 1,120 kg for a family of seven. We can also assume that to buffer years with poor production, Pueblo farmers likely planted a field large enough to feed that family for three years, or 3,360 kg of maize. The average MCG yields (1,728.80 kg/hectare) would require a field size of about 1.9 hectares to meet this need. The average yield from most productive campus garden—the Check Dam Garden—would require a field of 4.2 hectares to produce a three-year supply of maize for a family of seven. These figures can be compared to Ernest Beaglehole’s (1937, 37) observation that Hopi families in the early 1900s typically planted fields about 2.8 hectares in size.

In the preceding sections we described the differences between the MCG and campus gardens in terms of setting, soils, temperature, growing season, and precipitation. These differences result in the MCG garden having greater and more stable soil moisture, especially moisture deep in the soil profile. The difference in soil moisture translates into MCG yields that are four times greater than those from the combined average of the campus gardens. Hopi farmers noted that another factor that could contribute to higher MCG garden productivity is that this field had been rotated, with beans planted every third year, before we started planting there. Quantifying these variables and their effect on yields represents an important contribution of the PFP. But the dramatic differences in yields documented by the PFP also contribute to our understanding of ancestral Pueblo maize farming in the central Mesa Verde region and whether drought alone forced farmers to migrate from the region. We focus on three points here.

First, the consistently high yields from the MCG support an important point made by the computer models that estimate agricultural productivity in the central Mesa Verde region (Schwindt et al. 2016; Van West 1994). The best lands would have produced yields even during years when environmental conditions were significantly below average, including the late AD 1200s, when ancestral Pueblo people migrated from the region (see Kuckelman, chapter 19 in this volume for a discussion of environmental downturn and regional depopulation). For example, the summer of 2018 was among the driest on record in the Four Corners region. In fact, the ongoing megadrought since the year 2000 ranks as the driest period over the last 1,200+ years (Williams, Cook, Smerdon et al. 2022; Williams, Cook, Smerdon, Cook et al. 2020). Even during the 2018 drought, the MCG still produced significant yields (median: 1,019 kg/ha; mean: 1,032 kg/ha), whereas the Crow Canyon campus gardens produced only negligible yields. Even unprecedented drought—clearly the most important climate hazard for ancestral Pueblo maize farmers in the central Mesa Verde region—could not eliminate production on the best lands for maize farming.

Second, the central Mesa Verde region population peaked in the mid-AD 1200s, and this forced some farmers to cultivate areas with below-average productivity (Schwindt et al. 2016). Researchers argue that differences in productivity increased conflict and contributed to the depopulation of the region (Kuckelman 2010, 2016, chapter 19 in this volume; Schwindt et al. 2016). The MCG clearly represents exceptional agricultural land, and we believe farming occurred there during earlier periods because a large, late Pueblo I and early Pueblo II (AD 880 to 980) village, named the Gillota-Johnson site, lies just 650 m to the west. Reliable springs, abundant wild resources, and easy access to hunting in the uplands east of the Dolores River also characterize the locale. Yet virtually no thirteenth-century AD settlement occurs in this area. If competition for land forced some to cultivate marginal areas, why did ancestral Pueblo farmers avoid the prime lands around MCG that had been previously farmed? Was there some other factor that kept ancestral Pueblo farmers from cultivating this area? Answering these questions will be a focus of future research.

Finally, Hopi oral traditions provide information on the migrations that left the central Mesa Verde region depopulated at the end of the thirteenth century AD (Kuwanwisiwma and Bernardini, chapter 5 in this volume). Stewart Koyiyumptewa is a member of the Badger Clan, and clan history identifies the central Mesa Verde region as the clan’s homeland; he notes that when the Badger Clan migrated from the region, they were one of the last clans to arrive at the Hopi mesas. When asked about this migration, Stewart said, “You know, there’s theories about famine and drought. I think we could have survived here. We weren’t necessarily forced to go. It was a choice, to be part of this much bigger cultural group. They moved to join this one religious culture where the ceremonial calendar is divided by the ceremonies of the northern clans and those of the clans that migrated to Hopi from the south. That was why they left this area, to form this unique cultural system that combined the different clan groups from the south and the north” (Zoom meeting, March 17, 2021).

Initiated by the Hopi Cultural Preservation Office, the PFP investigates maize and maize farming as one of the central features of what Hopis call their “corn culture.” That corn culture also characterizes the other Pueblo nations, and corn is important to most Indigenous cultures of the Southwestern United States. For Crow Canyon, the PFP represents an important project that advances the Center’s mission by integrating research, education, and American Indian partnerships. The experimental farming component of the PFP has become the most thoroughly documented long-term experiment of its kind. The ability to sustain this project for fifteen years exemplifies Crow Canyon’s founding vision of supporting long-term research and education programs.

Note

1. 1. We report GDD in Fahrenheit units here. To convert to Celsius GDD, simply divide by 1.8.

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