When discussing deer management, much of the conversation centres around numbers, population density, cull ratios, male-to-female balance. Yet one of the most pressing questions we need to ask is not just how many deer are there? but what are they eating?
Recent feeding data from the South East provides a fascinating and, at times, sobering insight into the diets of fallow and roe deer. With over 300 plant species recorded, the results show a clear pattern: deer are not simply opportunists grazing here and there, but selective feeders shaping the very landscapes they inhabit. Understanding this is crucial if we are to make meaningful progress on sustainable woodland and farmland management.
Fallow Deer Consumption Calculator
Estimate vegetation consumed by fallow deer based on herd size and area. Defaults use 5 kg per deer per day.
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Note: Intake varies with season, habitat and body size. This tool uses a simple default of 5 kg per deer per day for quick comparisons.
Fallow Deer: The Generalist Grazers and Browsers
Fallow deer, abundant across Sussex and the wider South East, reveal themselves in the data as true generalists. Their top five food sources were:
Bramble (30.3%)
Perennial rye grass (10.2%)
Rough meadow grass (4.4%)
Yew (4.8%)
Wheat (4.2%)
With maize also appearing at 2.5%.
This spread highlights a critical reality: fallow are as comfortable in arable fields as they are in ancient woodland. By consuming rye grass, wheat, and maize, they place direct economic pressure on farmers. At the same time, their appetite for bramble, yew, and beech underlines their role in suppressing woodland regeneration.
Bramble, often regarded by landowners as a nuisance, is in fact a vital understory plant, providing cover and food for invertebrates, nesting birds, and small mammals. When deer strip it back, biodiversity suffers. Likewise, browsing of yew saplings threatens the long-term future of one of Britain’s most iconic and slow-growing native trees.
The implication is clear: unchecked fallow populations create a double bind, simultaneously eroding biodiversity value in woodland and economic yield in agriculture.
Roe Deer: The Selective Browsers
In contrast, roe deer — while smaller in body size — exert a disproportionate impact on woodland ecosystems. Their top five food sources were:
Bramble (58%)
Yew (4.5%)
Bluebell (2.8%)
Wheat (2.7%)
Holly/Field Maple (2.4%)
The dominance of bramble is striking: more than half of roe deer diet in this study came from this single plant. Bramble’s importance to woodland ecosystems cannot be overstated, yet roe consistently suppress it. Where bramble is lost, young saplings fail to establish, woodland birds lose nesting cover, and the ecological structure of woodlands collapses.
Their preference for yew, holly, and bluebell further compounds the problem. Bluebells, a defining feature of Britain’s ancient woodlands, are particularly vulnerable to over-browsing. The roe’s selectivity means that even at relatively low densities, they can have devastating effects on sensitive plant communities.
The Ecological and Economic Impacts
What makes this data compelling is not just the differences between fallow and roe diets, but the way the two species overlap and compound pressures.
Fallow exert a heavy toll on open ground and farmland, with significant consumption of rye grass, wheat, and maize.
Roe concentrate their browsing inside woodland, where their selectivity undermines regeneration of bramble, yew, and other key species.
Together, they present a formidable challenge: woodlands stripped of understory and regeneration, and farmland subjected to crop losses. The result is degraded ecosystems and financial strain on landowners and farmers alike.
Why This Matters for Deer Management
For too long, deer management has been measured primarily in terms of numbers culled versus numbers remaining. But numbers alone don’t capture the full picture. A relatively small roe population can prevent natural regeneration in a woodland, while a large fallow herd may devastate arable crops over a wide landscape.
Effective management requires us to tailor strategies to species-specific feeding behaviours.
For fallow, the focus must be on landscape-scale reduction, lowering densities to relieve both farmland and woodland.
For roe, targeted interventions in woodlands are critical, with attention paid to sensitive sites such as Ancient Semi-Natural Woodland (ASNW), Plantations on Ancient Woodland Sites (PAWS), and designated SSSIs.
This data also reminds us that collaboration between estates is essential. Deer do not respect boundaries. Where fallow herds range across multiple holdings, isolated management efforts are inevitably undermined by constant infill. Without cooperative management, pressure remains high and regeneration stalls.
Practical Implications for Landowners
If you are a landowner or agent in Sussex or the wider South East, there are a few key takeaways from this research:
Monitor feeding damage as well as deer numbers. Walk your woods and crops, look for browsing lines, stripped bramble, or grazed rye grass. Numbers don’t always tell the story, feeding pressure does.
Recognise the species-specific impacts. Roe may look less destructive than fallow at first glance, but in woodland their impact is profound. Fallow, conversely, can flatten arable yields while still exerting pressure on regeneration.
Invest in professional management. Recreational stalking alone, while valuable, is rarely sufficient. Structured, professional deer management ensures that culls are not only effective but strategically targeted at the species causing the most pressure.
Use data to support funding applications. Government schemes such as the PA7 Species Management Plan under Countryside Stewardship now explicitly require evidence-based approaches. Feeding data like this strengthens applications and helps justify professional interventions.
The Case for Incentivising Professional Management
Ultimately, feeding data reinforces what many of us in the sector already know: deer management cannot be left to chance. Without intervention, over-browsing will continue to erode both biodiversity and economic productivity.
Professional deer managers are essential to reversing this trend, but they must be supported. Incentives through schemes such as CWS1 grants and PA7 applications can help estates move away from purely recreational models of stalking towards structured, outcome-driven management.
At Wildscape, we have long argued that financially recognising the role of deer managers is key. Only by valuing this work properly can we deliver the scale of reduction required to restore balance to our landscapes.
Data as a Call to Action
The feeding data from the South East paints a stark picture: deer are reshaping our landscapes, not just by their presence but by their preferences. Bramble, yew, bluebell, rye grass, wheat , each tells a story of pressure, suppression, and imbalance.
But it also provides a roadmap. By understanding what deer eat, we understand where the impacts fall heaviest, and how to respond. For fallow, broad landscape reduction. For roe, targeted woodland intervention. For both, collaboration across estates.
At Wildscape Deer Management, we continue to combine practical field experience with the latest data to deliver effective, evidence-based solutions. If you are a landowner, agent, or farmer in Sussex or the wider South East and are struggling with deer impacts, now is the time to act. Together, informed by data, we can restore balance to both farmland and woodland.
