The problem with using manure in an organic system is that it has very poor traceability: it's almost impossible to get information about what the animals that produced the manure have been fed or what medication they may have been given.
Manure is often disposed of in piles, slurries or lagoons, which can lead to significant emissions of the greenhouse gas methane, as well environmental degradation, negative health impacts, and the loss of valuable nutrients that could be added to soil.
Manure has some potential disadvantages when used as fertilizer. It can contain weed and pest seeds, rodents and other pests, and pathogens such as E. coli. It can also cause pollution if not managed properly, as the manure may flow into the surface or groundwater.
The primary factors that affect nutrient composition of manure are livestock type, stage of growth and feeding practices (all of which determine nutrient excretion rates) as well as the amount of bedding or water added to the manure, type of manure storage, time that the manure spends in storage and weather conditions.
Manure is often linked to water quality problems. While nutrients from manure are not inherently more likely to cause water quality problems than nutrients from commercial fertilizers, some characteristics of manure make it more likely that nutrients can be over-applied to some fields.
Disadvantages of Manure
The manures are reported to provide fewer nutrients to plants, and they are unable to provide high-yielding crops. Manures are slowly absorbed by the plants, and they add a lot of humus to the soil. They are made in fields, so transportation is difficult for manures.
The biggest disadvantage of using an organic fertilizer is that it may not contain primary nutrients like nitrogen, phosphorous or potassium, also known as NPK. Manure-based fertilizers contain these nutrients and are still considered organic.
Sheep manure may just be the best poo in the world. It is a great soil improver and conditioner and contains lots of potassium that will strengthen the cell walls of your plants. Other cold manures include llama, alpaca, and goat, which are also low in nutrients but perfect for building up and improving your soil.
A disadvantage of composting is that some of the ammonia-nitrogen will be lost as a gas. Alone, compost may not adequately supply sufficient nutrients—particularly nitrogen during rapid growth phases of crops with high nutrient demands (e.g., watermelon, tomato, and pepper at fruiting) (Tyson and Cabrera, 1993).
Not all manure provides nutrients to plants. As it breaks down, manure containing lots of bedding takes nitrogen from the soil. This reduces the amount of nitrogen available to plants.
Don't Use Fresh Manure
If the manure is from a plant-eating animal, it is probably also full of weed seeds, which will not be inhibited from sprouting. If you still want to make use of fresh manure, don't apply it after your garden has been planted.
Manure is the organic matter added to the soil to increase its fertility. On the contrary, fertilizers are chemicals that are added to the soil to increase its fertility. Fertilizers might harm the soil, but manure is environment-friendly.
Manure contains nutrients, such as phosphorus and nitrogen, and pathogens, including bacteria, viruses and parasites. These pollutants contaminate water resources and reduce recreational potential of lakes and rivers, destroy wildlife habitat, and eliminate drinking water supplies for people and livestock.
Your better pick for veggie gardens? Compost! Although pasteurized or hot-composted manure should be free from disease-causing organisms, compost is still a safer choice for nourishing soil that will grow your food.
Animal manure applications can increase soil organic matter in medium / long term application periods. Consequently, manure contributes to reducing soil bulk density and compaction, as well as increasing soil aggregate stability, water infiltration and retention.
Dried cow manure has much higher nutrient levels - 2% nitrogen, 2% phosphorus, and 2.4% potassium—so you could use much less, roughly 10 pounds per 100 square feet. Fresh sheep manure is about 32% organic matter, has . 7% nitrogen, . 3% phosphorus, and .
Cow, horse, chicken/poultry, sheep, goat, and llama manure are acceptable types of manure appropriate for use in vegetable gardens. There are differences in using raw, aged, and composted manure in a garden. Manure may be composted in a variety of means, for the home gardener, this is usually hot or cold composting.
Horse manure has a higher nitrogen and nutrient content than cow dung. Moreover, horse waste contains significantly less water than cow manure; therefore, it can include up to twice as much nitrogen when dried. Horse manure requires composting or aging to kill weed seeds, larvae, and pathogens.
Manure contains many useful, recyclable components, including nutrients, organic matter, solids, energy, and fiber. With today's science and technology, we can use manure more efficiently and in more ways than ever. These techniques can protect water and air quality, and reduce greenhouse gases.
Organic manure improves the texture of the soil by not altering the pH of the soil. It has more moisture and organic content. Organic manure is usually derived from animal matter, animal and human excreta, and vegetative matter (e.g. compost and crop residues). As a result, it causes less damage to the environment.
Among the major environmental impacts may be contamination of soil, water, and air by nutrients, organic carbon (C), heavy metals, and pathogens, as well as air contamination by particulate matters, noxious gases, and pathogens.