Foxtail barley (Hordeum jubatum) receives its common name from its unique bushy inflorescence, or flower, which is similar in shape to the tail of a fox. This flower averages about two to five inches long and is soft and greenish or purplish. Its fluffy appearance comes from the awns, which can measure up to three inches long. Each yellowish-brown seed typically has four to eight awns, and it is also armed with tiny barbs along the edges. Read More
How well do you know your grass anatomy? You can probably identify a blade, a root, and maybe even an awn (ouch!), but how about a culm, a rachilla, or a panicle? Read More
Hard to believe that November is already just around the corner! Take some time on those chilly fall evenings to learn from nature and pull inspiration from innovative farmers and gardeners. And while you’re sitting at the table with family this Thanksgiving, remember to give thanks for the simple things.
- Learn lessons from the bison.
- Discover that you can farm.
- Eat your egg yolks.
- Explore the world of horse and donkey breeds.
- Witness the life of the tree in the trail.
- Pull ideas from the All New Square Foot Gardening method.
- Search for the roots of cattle driving.
- Try out 10 time-saving tips for the farm.
- Weigh in on the ongoing GMO debate.
- Give thanks for the simple things.
So what is an ideal brix level? Most plants show markedly improved vitality and pest resistance when their brix levels hit 12 degrees on a refractometer, although with care many can go far higher than that.
Increasing Brix in Produce and Pasture
Proponents of high-brix farming and gardening agree that soil microbe health is directly correlated with high brix levels in produce and pasture. Therefore, while chemical fertilizers can provide brief boosts in brix, they cannot maintain high levels over long periods of time unless special high-sugar hybrid plants are used. Organic fertilizers made to be applied directly to the leaves of the plant can also give a temporary increase in brix. In the long run, however, growers of heirloom and non-hybrid plants, whether they be food or forage species, must focus on feeding the soil.
Maintaining a balance of nutrients in the soil is an important step toward keeping microbes healthy and happy. If you are struggling with low brix levels, start with a soil analysis. Measuring NPK is not enough. It is important to know the levels of trace minerals, as well, because these are key to microbe health. Depleted minerals must be replaced.
Once the soil is brought back into balance, there are many options for keeping it that way. One of the most amazing soil and plant foods out there, according to refractometers across the nation, is raw milk. Pastures fed with raw milk can have a brix reading over 20 degrees! Grazing practices that allow for nutrient distribution and pasture recovery time tend to affect brix positively, as well.
Using Brix in Milk and Honey
Sometimes a quick fix is important when feeding milk to calves. If the brix levels fall too low (below 22% solids for colostrum or below 10% solids for whole milk), the calves will not thrive and mortality rates will increase. In this case, milk replacer or milk extender must be added to the milk. In the long run, managing the health of the dairy herd is important. Eliminating mastitis infections can make a big difference in milk quality.
Honey that contains a high proportion of moisture to sugar tends to ferment. Therefore, it should not be harvested until it measures 82 to 83 degrees brix (17% to 18% moisture on a honey refractometer). If for some reason the honey must be harvested before this point, the honey frames can be dried artificially with fans.
Now we have a definition of brix: the weight of dissolved sugar expressed as a percentage of the weight of the entire solution. The next question is how we measure brix.
As its name suggests, a refractometer operates on the principle of refraction. When a beam of light passes through a liquid solution, it bends, or refracts. The more solids (e.g., sugars) that are suspended in the solution, the more the light refracts. A refractometer is simply a device used to measure refraction.
Two types of refractometers are commonly sold:
- Analog or optical.
An analog refractometer uses a prism and an external light source to operate. A few drops of solution are placed on the prism, the refractometer is held toward a light, and the results are read on a scale.
A digital refractometer works on the same principle, but shines its own light on the prism from an LED. A sensor takes the measurement, a computer calculates the results, and a screen displays the brix reading.
Note that refractometers specifically sold for testing honey are made to display the inverse of a brix reading—that is, they display the moisture content of the sample and not the percentage of dissolved solids.
Shortcomings of the Refractometer
The reading displayed on the refractometer is actually not a true measurement of the sugar dissolved in the substance being tested. Any dissolved solids can cause light to refract; therefore all dissolved solids are included in the refractometer results. This includes minerals, proteins, and carbohydrates other than sugar, as well as other non-nutrient solids. Adding fertilizer to a glass of water, for instance, will change the brix reading according to the refractometer.
Of course, this may still help us reach our goals in measuring brix in the first place. After all, if we are measuring the brix of fruits and vegetables, whether from the store or our own backyard garden, we are using brix as a gauge of overall nutrient content. If there are more minerals in the produce, so much the better.
However, the main disadvantage of using the refractometer is that it cannot tell us exactly what is changing the reading. The only way to know for sure what sugars, minerals, and other solids are in our food or forage is to do a complete nutrient analysis—feasible in a livestock business, but a little too costly for everyday kitchen use.
Other factors that may influence refractometer results include:
- Sample preparation.
- Sample settling.
- Plant part tested.
- Ambient temperature.
Digital refractometers are programmed to compensate for some of these variables (particularly temperature). To ensure the most accurate results, however, try to test the same part of the plant at the same time of day in every test. Testing in similar weather conditions is also preferable.
Next week: How do we use brix?
Brix is one of those topics that come up fairly frequently in sustainable agriculture. Simply put, brix is a measure of the sugar content of a plant or other substance.
To be more specific, Brix expresses the weight of dissolved sugar as a percentage of the weight of the entire solution. Pure water has a brix of 0%. A solution of 5 grams of sugar to 95 grams of water would have a brix of 5%.
This measurement system was developed by and named for Austrian scientist Adolph Brix.
So how can this knowledge help us?
Advocates of high-brix farming and gardening say that plants with high brix levels are vibrant and healthy—and vibrant, healthy plants resist insect pests and diseases. They can also stand up to a light frost a little better.
High-brix fruits and vegetables generally have a sweeter, more appetizing flavor than their low-brix counterparts. However, brix proponents claim that there are other benefits to growing and eating high-brix foods. High-brix plants have a superior aroma and may be more digestible. They may even have higher nutritional content (some caveats next week).
Brix can be used to positively determine if a fruit is ripe, as the sugar content of a fruit increases dramatically while ripening.
Finally, high-brix produce keeps surprisingly well.
More Uses for Brix
But brix is not just a useful tool for those who grow plants. If you raise livestock, you can also benefit from monitoring brix:
- Beekeepers use brix to monitor honey quality.
- In dairy cattle, brix is used to evaluate the nutritional content of colostrum fed to calves.
- To all grazing animals, brix equals palatability. When given a choice, livestock will always choose high-brix forages over low-brix forages.
Some consumers also shop for brix these days, tapping into the nutritional benefits of high-brix foods. Besides testing fruits and vegetables for flavor and nutrition, they can also check honey and maple syrup for dilution.
Next week: How do we measure Brix?
Agriculture is very much a weather-dependent pursuit. The success or failure of both garden and field crops in any given year depends primarily on the rainfall and temperatures. Even pastures should be managed with an eye to the sky.
With this in mind, it is a good idea to know roughly what type of weather you can expect in an average year. Oregon State University has a series of 30-Year Normals maps of the United States that will be very useful to you as you pursue your country living adventure. This information can be critical in determining which practices make the most sense for your local climate.
Information displayed by the map includes:
- Mean temperature.
- Minimum temperature.
- Maximum temperature.
- Mean dewpoint temperature.
- Minimum vapor pressure deficit (a measure of the moisture saturation of the air).
- Maximum vapor pressure deficit.
Data can be viewed by month or as an annual average.
Great way to get a handle on your local climate!
Louisiana State University has put together an excellent website packed with countless building plans available for free PDF download. If you are the do-it-yourself type, this is a site that you should definitely bookmark!
Just to give you a very small sampling of the plans and projects that are included:
- Dairy parlors.
- Rearview mirrors for tractors.
- Walk-in refrigerators.
- Roadside fruit stands.
- Chicken coops.
The PDFs are simply diagrams—they do not contain step-by-step directions. However, dimensions are provided. With a little bit of building know-how, you should be able to get started without too much trouble.
While some of the plans are a little overkill for most country families (need an auction barn?), many of them will provide useful ideas for your construction projects, whether large or small. Highly recommended site!
TDN is short for total digestible nutrients. Many writers have criticized the term as being somewhat confusing, since TDN does not measure all types of nutrients, but rather the energy contained in a given feed.
TDN estimates are used for swine and horses but are most common in the ruminant world. Other methods of evaluating feed values are generally preferred for non-ruminants.
How TDN is Calculated
To be an accurate measure of energy, the TDN formula must factor in all of the nutrients in livestock diets that are capable of supplying energy. These are:
- Nitrogen-free extract (NFE). Better known to most of us as simple carbohydrates. Sugars and starches are highly digestible forms of carbohydrates, while fibers are generally less digestible. Fiber is not included in the nitrogen-free extract part of the equation. NFE is calculated as the percentage of feed that is not moisture, protein, fiber, fat, or ash.
- Crude fiber (CF). Fiber is the tough part of the plant, the part that gives it structure. Ruminants have specially designed digestive systems to break down fiber.
- Crude protein (CP). Protein is necessary for body maintenance, but any excess protein that an animal receives can be used for energy, as well.
- Ether extract (EE). Also known as crude fat. Fat is an extremely potent source of energy, so it is given greater weight than the other nutrients when calculating TDN.
To be able to calculate TDN, you will have to know the composition of the feed in question. You will also have to know how digestible the nutrients are—in other words, the proportion used for energy instead of being lost in the animal’s waste.
The formula is:
TDN = digestible NFE + digestible CF + digestible CP + (digestible EE x 2.25)
Another method of calculating TDN is based on the percentage of acid detergent fiber (ADF) in the dry matter of the ration. Some types of fiber are more digestible than others, and the ADF is the least digestible portion.
The formula for this method of TDN calculation is:
TDN = 96.35 – (%ADF x 1.15)
This method is older and less accurate than the formula above.
Forage samples can be submitted to a laboratory for analysis. The laboratory will tell you the amounts of the nutrients in the forage sample, and they will usually calculate the TDN, too. (But at least you now know how they figured it out!)
How TDN Numbers are Used
The principle behind TDN is that not all feeds and forages are created equal. Some feeds fill the animal’s gut, but provide it with very little of the energy that it needs to maintain its health, growth, and performance. Other feeds, however, are extremely efficient. A high percentage of their nutrients will be digested and used for energy. However, these efficient feeds can also be very expensive.
An animal’s TDN requirements change at different stages of its life. For example, dry females have much lower energy needs than lactating females. Fast-growing animals need more energy than slow-growing animals. Smaller animals will eat fewer pounds of TDN than larger animals, but the percentage of TDN relative to dry matter intake needs to be higher.
Admittedly, TDN calculations can make feeding livestock sound much more complicated than necessary. The general recommendation is to start by matching your animals’ needs to the growth cycle of your forage. Peaks in TDN requirements should coincide with peaks in pasture quality to achieve a low-cost feeding program. During periods of low forage availability, TDN once again comes in handy, as it can be used to determine if dormant or stockpiled grass is sufficient for your animals’ needs. If not, comparing the TDN of hay and supplements is a way to keep your costs down by avoiding overfeeding.
TDN has other shortcomings besides its complexity. It has been noted that TDN estimates of various feeds and forages tend to be rather optimistic. Also, TDN is just one piece of the pie. Animals have other nutritional needs besides energy. However, if you have doubts about your grazing or feeding program, TDN can be a helpful tool for preventing disaster.
Nutrient Requirement Tables
These tables from the University of Arkansas provide TDN requirements for beef cows, heifers, steers, and bulls of different sizes and stages of growth.
Nutrient Requirements of Sheep and Goats
TDN requirements are included for sheep and goats of different sizes and stages of growth.