Crop Rotation In Organic Farming
If a farmer plants the exact same crop in the same place every year, as is common in conventional farming, she continually draws the same nutrients out of the soil. Pests and diseases happily make themselves a permanent home as their preferred food source is guaranteed. With monocultures like these, increasing levels of chemical fertilizers and pesticides become necessary to keep yields high while keeping bugs and disease at bay.
Crop rotation in organic farming
Published by the Natural Resource, Agriculture and Engineering Service with funding from SARE, this manual provides an in-depth review of the applications of crop rotation specific the the Northeast. These applications include improving soil quality and health, and managing pests, diseases, and weeds. Consulting with expert organic farmers, the authors share rotation strategies that can be applied under various field conditions and with a wide range of crops.
How significant is a 50 percent reduction in nitrate leaching? Very! The goals of the Iowa Nutrient Reduction Strategy call for a 41 percent reduction in nitrate leaching across Iowa agriculture. Changing to an organic cropping system could by itself achieve the goals of the INRS for those farms that make that conversion.
It is good practice to not grow the same crop family on a piece of land more than once in every four years in crop rotations. Exceptions are when a fertility-building crop such as grass/clover ley is grown for two or three successive years or when a perennial or biennial crop is grown. This Soil Association (SA) factsheet provides guidance to help you plan and manage your crop rotations. It covers:
Regenerative organic farming is an approach to agriculture that utilizes ecological communities to build soil health and grow crops without synthetic inputs. Regenerative organic agriculture improves soil and biological resources by employing cover crops, crop rotations, and composting. In this way, it differs from standard organic farming practices. Learn how our CCOF-certified organic garlic farm is supplying nationwide.
Cash crops will be less likely to succumb to pests and disease with crop rotation and cover cropping systems. Many organisms can improve your farm ecosystem while also putting pressure on problems and diseases!
Depending on your soil type, soil properties can be improved in a number of ways. Cover crops can add organic matter, reducing tillage can minimize compaction, and bacteria can lower salinity. Fear not if you have less than desirable sandy, clay-filled or pesticide-saturated soil; with time and regenerative organic farming practices, you too can have healthy, productive soil! If your serious you must obtain a soil report. Laboratories are beginning to add more detailed reports such as water retention and microbiological activity
There are many ways to incorporate some form of composting into your agricultural practices. Compost can be derived from green (nitrogen), and dead (carbon) material and then added to the soil. Compost tea can be made to water or spray onto crops. Techniques for large-scale farming include utilizing no-till or minimum disturbance systems, cover crops, and grazing.
The real question is, why not? We use cover crops to build organic matter, suppress weeds, fix nutrients, feed bees and keep the soil covered during our rainy winters. Other farmers use cover crops to provide high-quality forage for grazing animals. You can even use a legume cover in your raised bed or potted plant to fixate nitrogen!
Crop rotation is essential for any farm looking to build soil health and crop resiliency and save money on nutrient inputs. Working a rotation into your agricultural plan might seem daunting at first, but many techniques are available to break the monotony in farming systems.
Crop rotations are, in simplest terms, a way to diversify food and shelter for your soil ecosystems and the foundation of regenerative organic agriculture. Farmers and gardeners who practice crop rotation will plant alternating crops on the same piece of land each growing season.
Soil persists as a temporal reservoir for phosphorus (P) in plant production, but only a relatively small fraction of total soil P is available for direct plant or microbial uptake. Inorganic and organic P forms in soils are a result of multifaceted P turnover processes which are affected by plants, microorganisms, and abiotic factors (Annaheim et al. 2013). As in organic farming crops are to be nourished primarily through the soil ecosystem (Council Regulation (EC) No 834/2007 on Organic Production), the farmers should contribute to maintaining and enhancing soil fertility. In organic farming, the recycling of wastes and by-products of plant and animal production (e.g., livestock manures, compost) and low soluble mineral fertilizers (e.g., rock phosphates) are permitted for P import. Furthermore, organic farmers try to foster biological processes in the soil for P mobilization by diverse crop rotations and organic fertilization. Nevertheless, many of them tolerate P budget deficits not knowing when soil reserves will be depleted (Gosling and Shepherd 2005). In organic agricultural soils in Europe, P is often enriched due to former application of inorganic and organic fertilizers (Tóth et al. 2014). This offers reserves for organic farms with low external feed and fertilizer import. But, continuous P budget deficits may lead to low plant-available P contents in soil.
In general, legume species were often described to mobilize poorly available P forms, mainly due to the exudation of organic acids, ions, and phosphatases (Li et al. 2007). The cultivation of legumes in crop rotations is therefore, besides being an important source of N, seen as a good opportunity to utilize soil P reserves.
Against this background, we expected that the soil P availability and enzymatic activity would behave differently in dependence of the farming systems over the study period. We hypothesized that under conditions of long-term negative P budget in organic farming, the decline in readily available soil P pools would be less pronounced in a dairy system (arable land and grassland) than in a stockless system (arable land). We believe this was due to the manure backflow to fields, the higher percentages of forage legumes, and longer soil cover during the year in the dairy systems.
Statistical analyses were conducted using R 3.2.2. Results on P fractions, total P, Porg, and activity of phosphatases and dehydrogenases from the focus areas of 2001, 2009, and 2013 were compared by pairwise t tests or, if data were not normally distributed, with the paired Wilcoxon signed-ranks test. The development of soil P(CAL) concentrations between 2001 and 2013 was analyzed using linear mixed-effects models. As the data were not normally distributed, they were log-transformed. For the data from arable land (dairy and stockless), the model was set up with year, farming system, and the interaction of these two as fixed effects and LTM point nested within LTM plot (see Fig. 2) and crop (Table 1) as random intercept effects. The model for the grassland data used year as fixed effect and LTM point nested within LTM plot as random intercept effect. The R package lme4 (R package version 1.1-8) was used for the modeling of mixed effects. Marginal and conditional R 2 were calculated for the mixed models by using the function r.squaredGLMM from the R package MuMIn (R package 1.15.1). While marginal R 2 deals with the variance explained by the fixed factors, conditional R 2 deals with the variance explained by the entire model (fixed + random factors). Least-square means (LS-means) were extracted after modeling using R package LS-means. A linear regression was performed based on LS-means for analysis of the development of P(CAL) over years in the farming systems. Possible relations between P in plants and P(CAL) in soils were analyzed by the Spearman rank correlation.
The mixed models for arable land and grassland had a marginal R 2 of 0.21 and 0.52 and conditional R 2 of 0.69 and 0.60, respectively. There are relatively high explanation rates of the variance with the entire models for arable land and grassland, whereas the different marginal R 2 indicate a higher explanation rate of the fixed effect (year) in grassland compared to the fixed effects (year, farming system) used in the model approach for arable land. Maybe this effect was due to higher variability of crops and to soil cultivation in arable systems compared to the continuous plant cover of soils in grassland.
Looking at possible effects of different crops, relatively high values of the labile inorganic P fractions were found after cultivation of legumes in arable land (Table 2) (see also Chapter 3.2). But neither the contents of the labile P fractions nor of P(CAL) contents in the focus areas of both rotations supported clear differences in development in both arable systems. With regard to the determination of labile P fractions, since only 3 years and a small number of samples were analyzed, possible effects of soil heterogeneity might have increased the variability of data. A more consistent trend could be derived from the higher number of data used for regression analysis of P(CAL) contents over all 12 years. Thus, to avoid overinterpretation of data from single events, we focused on general trends and a meaningful placement and discussion of the data within the system differences in the following.
The development of P(CAL) concentrations towards the minimum threshold in soil can contribute to an efficient utilization of P sources and the reduction of P losses in agroecosystems (Cordell et al. 2009). Similarly, Simpson et al. (2011) stated that managing soil fertility near the critical P level maximizes the P efficiency. So, mining P soil reserves as what happened in the systems of this study can replace the external P supply with fertilizers for a certain time span. However, in a long term, this practice is not sustainable and the P applications within a crop rotation should correspond to the P removal by crop harvests. For the grassland, however, the decrease of the relatively high initial soil P(CAL) values could have been useful to reach the range for the optimal P concentration and to reduce the risk of P losses. 041b061a72