David Doll0 commentsApril 25, 2022General

Re-evaluating operational costs for a difficult year

2022 will be a difficult year. Increased input costs, including water, fuel, and fertilizer, and decrease crop pricing will impact the operational expenses and crop revenues significantly. Many operations will struggle to maintain cash flows through the year. Operational costs should be closely evaluated to determine if savings are possible. Some expenses may be reduced on a short-term basis until pricing improves. Others may be eliminated from the current and future budgets due to more efficient management. A list of things to consider in helping reduce costs for the coming year include: Balance nitrogen rates. Typically, nitrogen budgets utilize a nitrogen use efficiency factor of 70%. By integrating more frequent, smaller applications of nitrogen, it is possible to assume a much higher utilization ratio – maybe closer to 85-90%. This could reduce nitrogen needs by 15-30 lbs/acre without impacting tree performance. Mid-summer leaf samples can provide feedback to this process (target range 2.2-2.5%). Test groundwater and accounting for nitrogen content. Groundwater in many parts of the San Joaquin Valley contains nitrate-nitrogen. If groundwater is used to irrigate orchard and it contains nitrate, make sure to account for the nitrogen and reduce the nitrogen budget. Balance potassium applications with any compost usage. The amounts of potassium and phosphorus within compost contribute to the nutrient budget of the orchard. Testing compost and accounting for moisture percentage should provide an estimate of the nutrients applied. This can reduce the need for fertilizers containing potassium and phosphorus (as well as many micronutrients). Review annual soil samples to determine if certain nutrients are not needed to be applied. It is common to see very high phosphorus amounts within CA soil samples and additional P may not be needed. Additionally, many loamy to clay containing soils contain potassium reserves. If the amount of potassium is high

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Franz Niederholzer1 CommentSeptember 9, 2013Nutrient

Sustainable Nutrient Management: a Review.

Almond harvest looks to be progressing well (knock, knock).  Orchard fertility/nutrition planning for the 2014 is beginning.  Now is a good opportunity to review the basics of almond orchard nutrient management.  While some of what follows will be review for many readers, a quick review may be of value. Sustainable nutrient management comes down to the four R’s – the Right Rate, the Right Time, the Right Place, and the Right Material.  A sustainable approach to orchard nutrition is intended to optimize crop production and maximizing net profit while reducing the risk of environmental contamination.

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David Doll8 CommentsAugust 17, 2013Nutrient

Postharvest Fertilization – Q&A

Q. How much nitrogen should be applied in the postharvest period? A. This depends.  This should be based upon the current tissue N levels detected from mid-July sampling. If within the prescribed ranges of leaf N (2.2-2.5%), 20% of the budget should be planned for application. If richer (>2.5%), slightly less can be added. If really high N leaf levels are observed (>3.0% in mid-July), postharvest fertigation may not be needed. 

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Franz Niederholzer0 commentsApril 20, 2013Nutrient

A quick review of UC ESP sampling for accurate almond orchard nitrogen fertilization.

This is the first year that the UC Early Season Protocol (UC ESP) model for predicting July almond leaf nitrogen (N) levels from April leaf samples, has been available for public use.  This model was developed by UC Davis researchers led by Dr. Patrick Brown.  Based on calls to several reputable ag labs and questions from PCAs, there seems to be some uncertainty about availability and use of the new model.  Where is the model?  How does is it used?  Who should use it to develop the July leaf N prediction and what should be done with the results?  Does an analytical lab run it for growers and PCA/CCAs?  If the lab doesn’t do it, should/can the grower or their PCA/CCA to do it, and, if so, where is the model?  This blog post is intended to answer these questions and help interested almond industry members use the UC ESP model.

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David Doll0 commentsApril 3, 2013Nutrient

Fertilizing Young Trees – First Year Trial Results

There have been several posts over the past few weeks about fertilizing mature almond trees. This data has been based upon long term studies held primarily in Kern County with some data points from across the state. Not all of this, however, is applicable to determining the rates of fertilization for developing almond orchards. At best, there are “educated guesses” in regards to identifying the proper rate for developing trees. Whole tree assays have found about 480 lbs of N/acre are stored within the woody biomass of mature trees. In order to reach that amount, trees would have to be accumulating nitrogen within the woody tissue at a rate of 20-50 lbs/acre/year until maturity (10-12th leaf). Once the tree begins to bear (~3rd/4th leaf), nutrients must be added to compensate for what is removed by the crop.

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David Doll7 CommentsJanuary 24, 2013Nutrient

Nutrient Removal for Almond

I have received a few inquiries about the nutrients removed for almond. Based on Dr. Patrick Brown’s group’s work (Sebastian Saa Silva and others), the amount of NPK removed with every 1000 kernel pounds of almond is: Nitrogen – 65 lbs, Phosphorous – 8 lbs, and Potassium – 76 lbs. This includes the nutrients removed will all of the materials exported out of the orchard in a typical pick-up operation – hulls, sticks, leaves, shells, and kernels. Keep in mind that more than the above amounts may be needed to compensate for the inefficiencies of application and uptake (i.e. nitrogen uptake efficiency is somewhere between 75-85%, condition dependent — so to have 65 lbs of uptake, 76-85 lbs of N must be applied). As noted in the comments below, potassium and phosphorous must be converted to oxides. This can be done as follows: Almond removal 8lbs of P = 18.4lb of P2O5 76 lbs of K = 91.2 lbs of K2O For Phosphorus o Lbs. P x 2.3 = lbs. P2O5 o Lbs. P2O5 x 0.43 = lbs. P   For Potash o Lbs. K x 1.2 = lbs. K20 o Lbs. K20 x 0.83 = lbs. K

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David Doll0 commentsApril 29, 2010Nutrient

Tips for Maximizing Nitrogen Use Efficiency for Almond

Previously this week, I wrote an article discussing nitrogen needs within the almond orchard. Application of nitrogen, as briefly discussed, varies in efficiency based upon techniques of application and irrigation/fertigation systems. Below are some tips to maximize efficiency and reduce losses for many common fertilizer application strategies. Maximize Efficiency:1. Apply N only when leaves are present and the tree roots are active. Avoid dormant season applications.2. Efficiency can be increased by applying N in small doses more frequently than large doses less frequently.3. Apply a uniform irrigation that is adequate to carry the N into but not past the root zone.4. Because young fruit trees have a fairly constant N uptake, apply multiple applications of N throughout the growing season.5. Mature trees need most of the N in the spring, around 70-75% of the nitrogen budget.6. Late summer/postharvest applications, 25-30% of the budget,will help with flower bud differentiation and formation for next year’s crop.7. Fertigation has generally been very efficient in N applications.8. Analyze leaves in July each year to fine tune N level to the orchard. Maintain the level in the adequate range. Minimize Losses:1. If fertilizer is surface applied, disc or irrigate N into the root zone shortly after application.2. Fertilize the tree, not the covercrop. Evaluate how best to bypass the covercrop. This may be by applying the fertilizer to the herbicide sprayed strip, mowing, or cultivating the covercrop.3. Don’t over irrigate. Nitrogen is soluble and moves with water. Excessive runoff of tail water or leaching will remove N.

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David Doll7 CommentsJuly 13, 2009Nutrient

Mid-July Leaf Sampling for Almonds

Leaf analysis of almond is a useful tool in diagnosing deficiencies, toxicities, and future nutrient needs of the tree. It provides an up to date analysis of the mineral composition of the tree, with desirable concentration of different elements known through extensive University of California research. Reasoning for sampling. As almond trees increase in size, their demand for nutrients also increases. Tree nutrient concentration is dependent upon the growth rate of the crop and the amount of nutrients that have been supplied naturally or through fertilizer. Under certain conditions, plant tissue may become deficient which could limit further growth and crop quality. Depending upon the nutrient and level of deficiency, remediation is possible in the current season, dormant period, or early spring of the following year. Leaf concentrations of major elements (nitrogen, phosphorous, and potassium) can be used along with kernel yield per acre to determine the nutrient budget for the next season. Process of sampling. Sampling should be distributed in a regular pattern across the block, with fully expanded leaves pulled from non-fruiting spurs on branches at least 6 feet high. About 100 leaves are needed for each sample. Leaves should be picked from trees of the same variety, age, rootstock, and soil type. Trees samples should be at least 100 feet apart and 20 trees are needed to ensure accuracy and confidence with the results. Partitioning of larger sampling blocks is advised to determine tree size and yield variability. Label the samples so the sampling location is known, and keep cool until they are sent to an analytical lab. Interpreting the results. Leaf analysis results are recorded either in percentages (%) or parts per million (PPM) of each element in a given weight of dried leaves. The table below contains the critical values for almond leaves sampled in

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