Cranberry Best Management Practice Adoption and Conservation Farm Planning in Massachusetts
Cranberry Best Management Practice Adoption and Conservation Farm Planning in Massachusetts
Carolyn J. DeMoranville1
ADDITIONAL INDEX WORDS. Vaccinium macrocarpon, BMP, american cranberry, wetlands, environment, nutrient management, nutrient load, fl ooding, nutrient discharge
SUMMARY. In Massachusetts, cranberry (Vaccinium macrocarpon) bogs were historically developed in existing wetlands and new plantings are now established in mineral soils that are converted into constructed wetlands. To streamline the interaction between cranberry farming and wetlands protection, the state has de- fi ned “normal agricultural practices” that are exempt from wetlands regulations under certain circumstances. As part of that process and to qualify for the exemp- tion, farmers are required to have a conservation farm plan and demonstrate the use of best management practices (BMPs) on their farms. The University of Mas- sachusetts Amherst Cranberry Experiment Station (UMass Cranberry Station) was engaged to bring together the U.S. Department of Agriculture, Natural Resource Conservation Service (NRCS) and cranberry industry representatives to defi ne BMPs specifi c to cranberry farming practices. Initially, the documents were reviewed by scientists and regulators for soundness of science and rigor of environmental protection. A grower committee reviewed the proposed BMPs to determine if the BMPs could be implemented on real farms. The next stage of the project consisted of defi ning areas where more research was needed to formu- late good BMPs. In particular, research projects were initiated to study nitrogen and phosphorus nutrition. This research has become the basis for nutrition BMPs, national cranberry nutrition guidelines, and standards used by NRCS for cranberry nutrient management plans. The cranberry BMP project has continued with a regular cycle of revision and additions based on grower-identifi ed needs for horticultural and environmental guidance. This connection to the growers, along with the regulatory link, accounts for the widespread adoption of BMPs in the cranberry industry. Local NRCS estimates that 75% to 80% of Massachu- setts cranberry growers have current conservation farm plans that include BMP implementation.
he cranberry is a long-lived national crop, with a farm-gate value woody perennial trailing non- of $47.4 million (National Agricultural Tdeciduous vine (Roper and Statistics Service, 2006). Production is Vorsa, 1997). Its native habitat is open concentrated in the southeastern area bogs, swamps, mires, wet shores, and of the state, contributing substantially headlands, and occasionally poorly to the local economy. In Massachusetts, drained upland meadows. The crop the third most densely populated state is cultivated in cool, moist, natural in the United States (U.S. Bureau of or artifi cial bogs that can be fl ooded the Census, 2000), cranberry pro- or drained as desired (Vander Kloet, duction is in direct competition with 1988). Historically, cultivation con- residential users for water and land sisted of the management of native resources, leading to increased scrutiny cranberry stands, including the instal- of horticultural practices and greater lation of drainage structures. Later, expectations for minimizing environ- cranberry beds were established on mental impact. wetland soils, characterized primarily With the advent of wetland as peat bogs, kettle ponds, or former outwash channels (Deubert and Ca- Units ruso, 1989). Cranberry production in To convert To convert Massachusetts accounts for ~23% of the U.S. to SI, SI to U.S., multiply by U.S. unit SI unit multiply by University of Massachusetts Amherst Cranberry 1233.4819 acre-ft m3 0.0008 Experiment Station, P.O. Box 569, East Wareham, 2.54 inch(es) cm 0.3937 MA 02538. 1.1209 lb/acre kg·ha–1 0.8922 1E-mail address: [email protected] 1 ppm mg·L–1 1
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July2006HT.indb 339393 6/7/06 10:57:26 AM protection laws and the prohibition Dike Dike of the conversion of natural wetlands Perched water table into cranberry beds, new cranberry bog construction techniques were * * * * * * * * * * introduced (Sandler, 1998). New Cranberry bog cranberry bogs are constructed with Sand (6-8 inches thick) a slowly permeable confi ning layer to Ditch establish a perched water table, thus creating an artifi cial wetland setting Organic confining layer (8-12 inches thick) within a mineral soil (Fig. 1). As these cranberry bogs mature, they function Water confining layer (variable thickness) as wetlands and fall under the same regulations as older beds. Activities in wetlands are regulated by state (Com- Native soil monwealth of Massachusetts, 2005a) and federal agencies. This presents a unique challenge to cranberry growers True water table who, by defi nition, are carrying out all of their horticultural activities in wetlands. In 1972, Congress enacted Fig. 1. Cross-section of a cranberry bog constructed in mineral soil, not to scale. legislation that came to be known as the Organic and water confi ning layers create a perched water table (adapted from DeMoranville et al., 2000); 1 inch = 2.54 cm. Clean Water Act (CWA). Section 404 of the act prohibited the discharge of fi ll into wetlands. As amended in 1977, (Commonwealth of Massachusetts, for Massachusetts cranberry farms. Section 404 defi nes agricultural activi- 2005b). For the various agricultural The Plymouth County Conservation ties in wetlands that are regulated, are enterprises in Massachusetts, a list of District, working with the local NRCS exempt, or that require a permit from normal practices was formulated and offi ce, began to develop cranberry- the U.S. Army Corps of Engineers became the list of exempt activities specifi c conservation farm plans. (Sandler, 1998; U.S. Environmental in the regulations developed under A conservation farm plan is a tool Protection Agency, 2003). Exempt the WPA. designed to help farmers manage their activities included normal agricultural By the 1990s, the U.S. Army land profi tably while protecting natural practices on existing farms that did not Corps of Engineers had recognized resources on the farm. The plan is de- impair or reduce the reach of a wetland. that cranberry farming is a water-de- veloped by a professional planner from Under these exemptions, cranberry pendent activity (U.S. Army Corp of the conservation district working with growers can continue to farm existing Engineers, 1992) and had adopted the the farmer to identify the resources on wetland bogs as long as they do not normal cranberry agricultural practices the farm, defi ne objectives for the plan, expand activities into other wetland list developed for the WPA as their list select actions to achieve the objectives, areas. New plantings in constructed of practices exempt from the CWA and evaluate the success of the planned wetlands fall under these same restric- Section 404 permit process [Cape activities. The farmer implements the tions once they are established. Cod Cranberry Growers Association plan. All design specifi cations in the (CCCGA), 2003a; Sandler, 1998]. plan must follow NRCS technical Wetlands Protection Act and Along with defi ning normal agricul- standards (CCCGA, 2003c). conservation farm plans tural practices, the U.S. Army Corps By the late 1970s, Massachusetts of Engineers developed BMP recom- Cranberry BMPs had enacted the Wetlands Protection mendations that must be followed for As cranberry farm plans were de- Act (WPA)(Commonwealth of Mas- some activities to be exempt. veloped and implemented, it became sachusetts, 2005b), which prohibited On the state level in Massachu- apparent that not all NRCS technical the fi lling, dredging or altering of land setts, the WPA provided for agricultural standards developed at the state and that bordered the waters of the com- exemptions. In the regulations associ- federal level were appropriate for the monwealth. Exceptions were given for ated with the WPA, the exempt activi- unique cranberry production system. “… maintenance of drainage and fl ood- ties that pertained to cranberry farming The CCCGA had begun working ing systems of cranberry bogs, to work were defi ned in two categories, those with the conservation district and performed for normal maintenance or that were entirely exempt (requiring no NRCS to modify the NRCS technical improvement of land in agricultural use action on the part of the farmer) and standards for use in cranberry farm or in aquacultural use ... .” The WPA those that could proceed if the farmer plans. At about that same time, the further provided for the Massachusetts had a conservation farm plan on fi le UMass Cranberry Station was prepar- Department of Food and Agriculture, with the local conservation commis- ing to produce an updated guide to with input from a committee consisting sion (CCCGA, 2003b). This provision, Massachusetts cranberry production of representatives of UMass Extension, combined with the requirement of a practices and Ocean Spray Cranber- NRCS, and farm operators, to estab- farm plan to allow a grower to partici- ries, Inc. (Lakeville–Middleboro, lish defi nitions for the term “normal pate in federal cost-share conservation Mass.) was beginning the process of maintenance or improvement of land programs, was the impetus for the providing best management practices in agricultural, or in aquacultural use” conservation farm planning initiative guidelines to its growers. All of these
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JJuly2006HT.indbuly2006HT.indb 339494 66/7/06/7/06 110:57:270:57:27 AAMM groups came together to identify a working group consisting of cranberry The soil testing research identifi ed unifi ed project that was submitted research and extension professionals soil iron as an interfering factor when to the Massachusetts Department of from the growing regions of North using the Bray test in cranberry soils Food and Agriculture Agro-Environ- America has taken on the challenge but did not identify an alternative test. mental Technology Program. The of developing nutrient management Current research continues to address Best Management Practices Guide for guidelines for nitrogen (N) and phos- these issues. Massachusetts Cranberry Production phorus (P) use in cranberry produc- The effect on water quality from was the result of that partnership tion, initiating research projects, and N and P use in cranberry production is (DeMoranville et al., 2000). developing publications providing a concern in Southeastern Massachu- Each section of the guide begins guidance to growers (Hart, 2000; setts where many cranberry farms are with a description of the part of cran- Roper et al., 2004). located. While nutrient inputs are fairly berry production addressed in that Nitrogen management is critical in modest, cranberry production is very BMP. Following the introductory sec- cranberry crop production. However, water intensive. Cranberry produc- tion is a series of recommended prac- the N requirement is modest, between tion requires 5 to 10 acre-ft of water tices designed to maximize productivity 22 and 67 kg·ha–1 per year, and high N from all sources. Production practices, while preserving the environment. rates, particularly early in the season, particularly those involving fl ooding BMPs for the guide were compiled can lead to an abundance of vegeta- of the beds, can lead to discharges of based on existing science and balancing tive production at the expense of fruit bog waters through surface water fl ow good horticultural production prac- production (Davenport, 1996; Daven- directly to streams, ponds or lakes. Re- tices and environmental stewardship. port and Vorsa, 1999; DeMoranville, cently, a research project to study the The documents were then reviewed 1992). Like most ericaceous plants, output of N and P from cranberry bogs by representatives of grower organiza- cranberries preferentially use ammo- was completed. As part of that project, tions, cranberry handlers, NRCS and nium N. Although limited quantities cranberry growers identifi ed three bog the conservation district. Specifi cally, of nitrate can be taken up by the plant, pairs with similar soil characteristics and growers were charged with comment- nitrate reductase activity in cranberry management within pairs. They agreed ing on the practicality of implementing is extremely limited (Smith, 1993). to voluntarily reduce P input onto one practices on their farms. By taking this In addition, populations of nitrifying bog in each pair so that the impact on approach, the likelihood of adoption bacteria are low in acidic cranberry fl ood discharge water quality could be of the BMPs was increased. The use soils (Davenport and DeMoranville, evaluated. When N and P load in source of the BMP guide as part of the farm 2004). BMP recommendations for N waters was compared to that in water planning process also encouraged BMP management include monitoring soil leaving the cranberry bogs at these six adoption. temperature for planning applications, sites, the bogs were net importers of The cranberry BMP guide con- using moderate rates and split applica- N and net exporters of P (Table 1). tinues to undergo a regular cycle tions, maintaining acidic soil pH, and At these sites, P export ranged from of revision and additions based on monitoring plant status by evaluating >1% to 23% of that applied in fertilizer. grower-identifi ed needs for horticul- growth and tissue test N (DeMoranville At two of the sites (sites 1 and 5), P tural and environmental guidance. This et al., 2000; Hart, 2000). fertilizer inputs were reduced by at connection to the growers, along with Phosphorus management rec- least 35% by the end of the third year the regulatory link, has accounted for ommendations for cranberry were (Table 2). At those sites, P discharge the widespread adoption of BMPs by published (Roper et al., 2004) based declined substantially after two years the Massachusetts cranberry industry. on completed research studies regard- of reduced rates (Table 1, sites 1 and The CCCGA has reinforced the need ing rates, timing, and soil P testing 5, compare 2002 to 2004). In fact, for farm planning and BMP adoption (Davenport et al., 1997; DeMoranville the bog became a net P importer at with its members by issuing grower and Davenport, 1997). These studies site 5. During the period of this study, advisories highlighting the advantages identifi ed 22 kg·ha–1 as a suffi cient rate P fertilizer reduction had no adverse of these activities (CCCGA, 2003a, for annual P use in cranberry but did effect on crop yield. Mean yield for 2003b, 2003c). Local NRCS estimates not determine lower effective rates. the two seasons prior to planned P that 75% to 80% of Massachusetts cranberry growers have current con- Table 1. Net discharge of phosphorus (P) and nitrogen (N) in cran- servation farm plans that include BMP berry bog water. Net discharge equals gross discharge minus nutrient implementation (L. Rinta, personal load in source water. communication). Total P (kg·ha–1 per year)z Total N (kg·ha–1 per year) Cranberry nutrient Site no.y 2002 2003 2004 2002 2003 2004 management 1 1.29 2.59 0.60 ---x –7.24 –9.56 As part of the BMP development 2 3.30 3.62 2.43 --- –7.04 –15.34 process, management practices were 3 3.44 1.58 1.03 --- –0.16 –1.92 identifi ed for which knowledge was 4 4.15 2.76 4.30 --- –5.80 0.55 insuffi cient for the defi nition of exten- 5 0.01 0.06 –1.24 --- –9.13 –25.14 sive BMPs. A primary area requiring 6 0.27 –0.63 0.19 --- –15.91 –15.98 additional research and synthesis of z1 kg·ha–1 = 0.8922 lb/acre. recommendations was cranberry nutri- ySites 1 and 5 implemented planned P fertilizer reductions beginning in 2003 (Table 2). ent management. A mineral nutrition xData not collected.
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JJuly2006HT.indbuly2006HT.indb 339595 66/7/06/7/06 110:57:270:57:27 AAMM Table 2. Fertilizer phosphorus (P) and nitrogen (N) inputs applied to Table 3. Yield at cranberry bog sites cranberry bog study sites from Table 1. Study protocol called for up from Tables 1 and 2. Planned fertil- to 50% P reduction (from 2002 rate) in 2003–04 at sites 1, 3, and 5. izer reductions (Table 2) were made in 2003–04. Fertilizer P Fertilizer N (kg·ha–1 per year)z, y (kg·ha–1 per year) Mean yield (kg·ha–1)z Site no. 2002 2003 2004 2002 2003 2004 Site no. 2001–02 2003–04 1 20.0 16.1 6.3 35.1 36.4 33.2 1 12,432 16,352 2 27.9 25.0 19.4 44.2 36.4 40.7 2 14,448 17,696 3 22.4 18.1 19.6 38.7 42.0 29.6 3 14,672 14,896 4 22.4 20.6 18.8 42.0 42.0 30.3 4 12,096 11,312 5 32.2 22.2 23.7 68.6 38.0 61.1 5 20,944 19,936 6 39.8 36.3 31.4 60.6 44.8 53.9 6y 16,016 23,968 z1 kg·ha–1 = 0.8922 lb/acre. z1 kg·ha–1 = 0.8922 lb/acre = 0.008922 barrel/acre. yExtension recommendations for non-defi cient cranberry beds call for up to 22 kg·ha–1 P and 22–67 yCrop at this site was severely reduced in 2001 due to kg·ha–1 N per year. insect infestation.
reduction was not different from 0.14 A Incoming Total P A that for the 2 years of modifi ed 0.8 0.12 On bog Total P management (Table 3). Discharge Total P
(ppm)] 0.10 Data indicated that fl ood dis- -1 L .
charges were generally the source (ppm)] 0.6 0.08 -1 L for the majority of P output from . the bog systems. Most cranberry 0.06 bogs are fl ooded for harvest and for 0.4 0.04 Incoming winter protection. A previous study On bog 0.02
of a cranberry bog system (Howes PO4-P in water [mg Discharge
and Teal, 1995) also showed that 0.00 0.2 Total P in water [mg N and P discharge from cranberry bogs was primarily associated with 0.35 B 0.0 fl ooding. Therefore, nutrient loads 0.30 associated with fl ooding events (ppm)] 0.25 -1 Incoming PO4-P B L were more closely examined. . 0.8 On bog PO4-P Figure 2 shows a typical harvest 0.20 Discharge PO4-P fl ood in which the water was held 0.15 only briefl y prior to discharge. (ppm)] 0.6 -1 L Note that the water held on the 0.10 . bog during harvest (day 1 and 0.05 2) had an increased nutrient load water P in Total [mg 0.4 compared to that in the incom- 0.00
ing water and that this load was 1.8 0.2 somewhat reduced by the time of 1.6 C PO4-P in water [mg discharge on day 2.5 (Fig. 2). The 1.4
early fl ood nutrient increase was (ppm)] -1
L 1.2 likely due to particulates becom- . 0.0 0 5 10 15 20 25 ing suspended in the water during 1.0 Time after flood (d) agitation by the harvest equipment 0.8 while decreased P concentration 0.6
in the discharge was likely due to 0.4 Fig. 3. (A) Total phosphorus (P) and
particles settling or being fi ltered (B) phosphate (PO4-P) concentration
Total [mg in water N 0.2 by the outlet fl ume. in cranberry-bog harvest fl ood water 0.0 sampled from site 1 in 2002. Flood Figure 3 shows data from 0123 a harvest fl ood at site 1 in 2002 discharge began on day 12. Data Time after flood (d) points represent single samples, all project data was collected according to a quality assurance plan that required Fig. 2. (A) Inorganic phosphate (PO4-P), (B) total phosphorus (P), and (C) total nitrogen that duplicate nutrient samples not (N) concentration in cranberry-bog harvest wa- exceed 20% relative percent difference. ter sampled from site 5 in 2003. Flood release occurred on day 2.5. Data points represent single samples; all project data was collected according to a quality assurance plan that required that duplicate nutrient samples not exceed 20% relative percent difference.
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JJuly2006HT.indbuly2006HT.indb 339696 66/7/06/7/06 110:57:280:57:28 AMAM where harvest fl ood management was Deubert, K.H. and F.L. Caruso. 1989. modifi ed to test two potential BMP Literature cited Bogs and cranberry bogs in southeastern recommendations: 1) P discharge Cape Cod Cranberry Growers Association. Massachusetts. Mass. Agr. Expt. Sta. Res. could be reduced if the fl ood was 2003a. Grower advisory: Cranberry pro- Bul. 727. retained for an extended period after duction practices and the Federal Clean Hart, J. (ed.). 2000. Nitrogen for bearing harvester agitation to allow settling Water Act. 11 Apr. 2006.
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