Film bound bales promote consistent crop preservation

Film bound bales, using 3D wrapping and Intelliwrap, are better preserved than bales bound with net and conventionally wrapped in multiple layers of film. This is the main finding
of a study carried out in 2021 and 2022, conducted by Kuhn in cooperation with Eurofins Agro in Wageningen. Intensive sampling of both types of bales investigated the feed value
and preservation quality.

After six weeks of storage (July 2021), no significant differences in the feed value and preservation quality were found between net bound and film bound bales. However, after eight months of storage (February 2022), the film bound bales had a significantly lower butyric acid concentration than the net bound bales. According to Bob Fabri, feed and preservation expert at Eurofins Agro, the beneficial bacteria in the film bound bales dominated, resulting in a clearly better preservation quality of the bales. This superior preservation was further demonstrated by the almost negligible presence of mould formation in the film bound bales, contrary to the net bound bales. The shape retaining stability of both bale types were similar.

Film binding in addition to net binding

In recent years, the techniques used to bale and wrap round bales have been increasingly refined and enhanced. Three key developments are the introduction of film binding in addition to net binding, and 3D wrapping and Intelliwrap technologies (see boxes). A practical trial performed in 2021 examined the benefits of these three developments.

Net binding versus film binding

The goal of the study was to compare bales bound with net and conventionally wrapped in several layers of film, with bales bound with film and wrapped in film, using 3D wrapping
and Intelliwrap. The subject of the study was therefore two groups of bales that were compared according to the following parameters:
• Feed quality (determined by Eurofins Agro)
• Mould formation (visually assessed)
• Shape retaining stability of the bale (visually assessed)

The main question to be answered by the research was: what is the difference between a conventional net bound and wrapped bale (6 layers of film) compared with a film bound
and 3D wrapped bale (5 layers of film)?


Intelliwrap is the system developed by Kuhn that, by varying the rotational speed of the round bale during wrapping, enables the number of layers of film used to wrap the bale to be precisely controlled. In other words, both even and odd numbers of layers can be applied. This process takes place fully automatically after the number of layers of film required is entered on the terminal. The rule of thumb is that the drier the crop is harvested and the longer the intended storage period, the more layers of film should be applied. The table shows the number of layers of film required for a bale based on both parameters.

12 hectares cut and ensiled

In June, 2021 12 hectares of grassland (4-5 years, perennial ryegrass, sandy soil) were cut and ensiled at the farm owned by Jos Kuypers in Aarle-Rixtel (the Netherlands). All the bales were baled, bound and wrapped with the Kuhn FBP 3135 fixed chamber baler-wrapper combination. The film thickness was 25 mu, the film colour was Eco-Green.
Group 1: bales bound with 2.75 layers of net and conventionally wrapped with 6 layers of film
Group 2: bales bound with 3 layers of film and wrapped with
5 layers of film using 3D wrapping and Intelliwrap

Whilst baling, grass samples were taken by crop research Organisation Eurofins Agro for the purpose of analysing the feed value. In addition, a composite sample was also created by
combining samples taken from various swaths. Forage quality samples were taken by Eurofins Agro after a period of 6 weeks. Two composite samples were taken per
group of bales: one for feed value analysis and one for conservation analysis. Material was sampled/probed from 4 bales in each group. After 8 months (February 2022), quality samples were taken again from each group of bales: one for feed content analysis and one for conservation analysis. The purpose of taking these samples was to determine how much feed value had been lost from the bales during the storage period. During the second round of sampling, probes were inserted into the same bales used during the first round of sampling, but the samples were taken from the opposite side of the bale. When the bales were opened, a visual assessment was made of the amount of mould present and the location of any mould patches in the bales. An assessment form was completed for each bale, that used the following criteria to assess mould formation: location per patch of mould, number of patches of mould and volume of mould per patch. The criteria were scored on a scale of 1 to 10, whereby 10 is the highest score (no mould anywhere in the bale). Only film was applied to one type of bale, while net and film were applied to the other type of bales. During the study, therefore, the binding and wrapping costs of both bale types were compared separately.

Less butyric acid after 8 months of storage

The analysis results of the first composite sample taken during baling in June 2021 are shown below:

The results of feed content analysis and conservation analysis of the samples taken from both bale groups after 6 weeks (July 2021) are shown below: