In our conditions, hay and straw are mainly pressed. The criteria are different in an agricultural company that presses for its own use of animal production, and different for service companies that supply heavy bales for the needs of an incinerator. In terms of transport logistics, the weight and size of the package play a big role here. Today we will focus on the needs of animal production and its subsequent storage.
For square bales, it is crucial to ensure that they are cleaned from the field under the roof, especially if we are baling hay, it must not get wet under any circumstances. Here there is a risk of immediate intrusion of water and moisture into the already harvested material. There i salso a difference with round bales wrapped in netting (where the surface will drain rainwater better from the surface due to the denser coverage of the netting). Storage of parcels under the roof is to be considered if they are to be resold or stored for a long time to maintain the best value and quality. There are of course several other ways to store bales directly in the stack in the field. It is good to put a layer of loose straw (or blown straw) on the top of the stack, unless we plan to cover it with a tarp.
An example of inappropriate straw storage. Here there was a strong inflow of water into the stacked bales, resulting in losses.
It is essential to place the bales at the top of the ridge and close the tarpaulin well so that the rainwater drains away and does not form pools that can gradually seep in through the tarpaulin (which can become damaged, scratched or punctured over time). If the sail is well off, even a little bit of a hole in the sail is not so much a problem, the amount of water that flows through the holes in the taut sail is not so critical. The sail should be as strong as possible. Ordinary PE tarpaulins can also be used to cover silage pits or tarpaulins designed to cover stacks with a minimum weight of 200 g/m2 (we recommend choosing heavier weights). They are finished with either a metal mesh or an overlay. Subsequently, the sails will be loaded and secured against the wind.
In recent years, a new technology of storing straw pressed into large square bales in stacks covered only on the surface with transparent stretch film has begun to be applied. The main advantage over existing stacks is the creation of a sleeve with foil, with the fact that there is no full hermetic closure, then the front and the back sides remain exposed and serve for free air flow. This technology is also suitable for stacking packages with higher humidity up to 25%, when the subsequent free flow of air reduces the humidity. This achieves the goal of maintaining better quality and calorific properties of the straw in the process during subsequent combustion. For energy use by combustion or for the production of heating pellets, these packages are better used and sought after by processors. According to experience so far, losses during free storage of baled straw range up to 25%. (this data is based on the measurement data of Ing. Zdeněk Abrham, CSc. Research Institute of Agricultural Technology Prague).
For hay, it is necessary to immediately remove it from the field and store it preferably under a roof, it must not get wet.
Straw bales are not as sensitive to getting wet and also for later subsequent storage.
An example of the correct layering of bales in the upper part followed by covering with a tarpaulin.
The same stack with bales photographed at the beginning of spring of the following year. Package quality maintained.