Farmyard Manure and Organic Matter in Hazelnut Orchards: Building the Foundation

Why Farmyard Manure Deserves Its Own Article

When fertilizer comes up in hazelnut growing, nitrogen comes first, then phosphorus and potassium. Yet what determines how long those three elements stay in the soil is not the fertilizer itself but the soil’s organic matter content.

Hazelnut land in the Black Sea region is sloping, rainy and prone to leaching. On such land, a soil low in organic matter cannot hold what you apply: nitrogen leaches away, surface runoff carries fertilizer off the orchard, and in dry weeks no water is left in the root zone. That is why farmyard manure is not “one more fertilizer” — it is the foundation that makes every other fertilizer work.

This article expands the single line about farmyard manure in our fertilization programme.

What Organic Matter Does in the Soil

Organic matter is the dark, spongy material left behind when plant and animal residues decompose. It makes up only a small percentage of the soil, yet its effect is disproportionately large:

• Water holding. Organic matter holds many times its own weight in water and releases it slowly. The orchards that suffer first in a summer drought are the ones lowest in organic matter.
• Nutrient holding (cation exchange capacity). Organic matter surfaces hold calcium, magnesium, potassium and ammonium electrically, slowing their loss to rainfall. The higher the cation exchange capacity, the more yield the same fertilizer delivers.
• Soil structure. It glues soil particles together into aggregates. The result is a more porous, better-aerated soil that is easier to hoe.
• Microbial life. It is the carbon source for soil bacteria and fungi. Without organic matter, microbial activity falls and mineralisation — the conversion of nutrients into plant-available forms — slows down.
• Erosion resistance. Aggregated soil resists raindrop impact and surface runoff far better. On sloping hazelnut land this directly means less soil loss.

Where Do Black Sea Hazelnut Soils Stand?

Soil fertility studies in the region’s hazelnut orchards point to a consistent picture.

In samples taken from the 0–30 cm layer of 71 hazelnut orchards across 40 villages in the Kumru district of Ordu, soils were generally found to be clayey, salt-free and of medium organic matter status, while total nitrogen, available phosphorus, exchangeable potassium and zinc were deficient. Soil pH in the same study ranged from 4.53 to 7.87 — meaning that even within a single district, orchards differ enormously. 📚 Karadeniz & Özkutlu (2023) - Academic Journal of Agriculture

Another study covering Ordu and Giresun provinces found total nitrogen and exchangeable calcium and magnesium adequate, while available phosphorus and exchangeable potassium were insufficient.

Read together, the message is this: the regional problem is usually not “there are no nutrients in the soil” but that nutrients cannot reach the plant and cannot stay in the soil. Organic matter and pH sit right in the middle of both bottlenecks. That is why farmyard manure and liming complement each other.

Do not guess your own orchard’s organic matter percentage — read it from a soil analysis report. How to interpret the organic matter line is explained in that article.

What Farmyard Manure Gives — and What It Does Not

The nutrient content of farmyard manure is not fixed. Manure from two barns in the same village can differ several-fold. The main reasons:

Source of variation	Effect
Animal species	Poultry manure is far stronger than cattle manure and must be used in smaller amounts
Feed regime	Animals use only part of what they eat; the remaining nutrients pass into the manure via dung and urine
Bedding material	The more straw, sawdust or soil in the mix, the lower the nutrient density and the higher the carbon ratio
Whether urine is retained	A large share of the nitrogen is in the urine; urine that drains away takes nitrogen with it
Storage method and duration	A heap left in the open loses nutrients to rain; loosely stacked “hot” manures contain more nutrients than compacted “cold” ones

📚 Bayburt Provincial Directorate of Agriculture and Forestry

The contrast with mineral fertilizers is clear. Urea contains 46% nitrogen and potassium sulfate 51% K₂O — known figures guaranteed on the label. The content of farmyard manure can only be known through laboratory analysis, and it changes with every batch.

	Farmyard manure	Mineral fertilizer
Nutrient density	Low and variable	High and label-guaranteed
Speed of effect	Slow, spread over years	Fast, within the same season
Organic matter contribution	High — this is its real benefit	None
Effect on soil structure	Marked improvement	None
Ease of calculating a rate	Difficult without analysis	Easy

Well-Rotted Manure vs. Fresh Manure

This is the single most critical point. As the Hazelnut Research Station’s farmer training publication states plainly: unrotted barn manure contains diseases, pests and weeds; applying it can bring disease and pest problems and increase the weed load. For that reason, manure taken into the orchard must be well rotted.

Fresh manure carries four distinct risks:

1. Weed seed. Seeds that pass alive through the animal’s digestive system are effectively sown into your orchard.
2. Pathogens and pests. An immature heap allows disease organisms to survive.
3. Nitrogen hunger. Fresh manure has a high carbon-to-nitrogen ratio. Once worked into the soil, microorganisms consume soil nitrogen to break down that carbon, and the tree is temporarily left without nitrogen. Rotting lowers the carbon/nitrogen ratio and removes this risk.
4. Root burn. Ammonia and soluble salts in fresh manure can scorch the fine roots they touch.

How to Tell Manure Is Well Rotted

• The colour is dark brown to black; the original yellow-green tone has gone
• The smell is earthy, like a forest floor, not sharp ammonia
• The structure crumbles; straw and bedding are no longer recognisable
• The inside of the heap is the same temperature as the outside — no warmth when you reach into it

How to Let the Heap Mature

Provincial directorate publications describe two classic methods:

• Hot heap method: The manure is stacked loosely so air can enter. Heap temperature rises to around 60 °C, reached in roughly 1 week in summer and 15–20 days in winter, and the manure is ready for use in about 3 months.
• Cold heap method: The manure is compacted and rots under anaerobic conditions; the temperature does not exceed 30 °C. Slower, but with lower nitrogen losses.

In both methods the heap must be protected from rain and drainage water; that is where most of the nutrient loss happens.

When to Apply

The Hazelnut Research Station’s fertilization calendar places animal manure in the November–March window. The logic:

• The soil is moist, so decomposition starts as soon as the manure is worked in
• The tree is dormant, so hoeing in the root zone causes the least damage
• It takes months for organic matter to become plant-available — manure applied in winter is working by spring
• Winter soil work does not clash with the busy spring schedule

Why not spring? Manure applied in spring cannot catch the peak demand period, and late hoeing in wet soil both wounds roots and compacts the soil.

How to Apply

The method matters as much as the amount. The Hazelnut Research Station is specific: animal manure is spread into a circular band 30–40 cm wide under the canopy projection and worked into the soil.

Three points deserve special attention:

Canopy projection. The fine absorbing roots are not at the trunk base but under the drip line of the branch tips. Manure heaped at the trunk is both wasted and a rot risk at the root collar.

Incorporation. The same publication states that lime, animal manure and nitrogen fertilizer must always be hoed into the soil after application. Manure left on the surface loses nitrogen to the air, never contacts the soil, and washes away in the first heavy rain.

Sloping ground. The same source notes that on slopes the root system is distributed more heavily downslope, while on flat ground it is even. On a sloping orchard, distribute the manure asymmetrically, following the downslope root concentration. Keep the gap between spreading and hoeing short, and do not apply when heavy rain is forecast.

How Much to Apply

There is no single correct figure here; sources use different scales.

Source	Recommendation
Hazelnut Research Station (2013)	November–March, a 30–40 cm band under the canopy projection, worked into the soil (amount left to soil analysis)
Bayburt Provincial Directorate	1–4 tonnes per decare, depending on the crop
Our own fertilization programme	25–30 kg of well-rotted manure per bush (2–3 tonnes per decare), every 3–4 years

When setting the amount, weigh three variables together: tree age and canopy width (a young bush takes less), the soil’s current organic matter percentage (use the upper end of the range if the analysis is low) and the quality of the manure (a light, bedding-heavy manure needs to be applied in larger amounts).

As a practical rule for frequency: do not apply every year. Organic matter breaks down over several years; stacked applications lead to salt build-up and wasted money. Every 3–4 years, run alongside a soil analysis repeated at the same interval, is the soundest pattern.

If Farmyard Manure Is Unavailable: Alternatives

In villages where livestock farming has declined, farmyard manure has become hard to find. There are other ways to close the organic matter gap.

Hazelnut Husk Compost

This is the most sensible option because it recycles a waste the orchard already produces. In a field trial in Bulancak, Giresun, on the Tombul variety, compost made from husk and pruning waste by the windrow method was worked in 50 cm wide and 15 cm deep under the canopy projection. The results:

Compost rate	Yield (kg/bush)	Increase over control
Control (0)	1.89	—
0.5 t/da	—	74.07%
1.0 t/da	3.68	94.71%
1.5 t/da	—	84.65%
2.0 t/da	—	72.48%

The highest yield came from the 1.0 t/da rate; at higher rates the relative gain fell back. The researchers recommend applying compost made from post-harvest waste at 1.0 t/da. 📚 Yavuzkılıç & Gülser (2024) - Journal of Soil Science and Plant Nutrition

In the same study, organic matter content was measured at 92.97% in the husk and 96.35% in the pruning waste; husk is an extremely rich source of organic matter. Because its carbon/nitrogen ratio is high, however, it must not be worked into the soil directly — it has to be composted first. The Samsun Provincial Directorate describes spreading husk in roughly 20 cm layers, adding well-rotted barn manure and agricultural lime to each layer and moistening it, with maturation completed in 6 months to 1 year.

Green Manuring

This means sowing a legume between the rows and working it into the soil at flowering. On sloping land it brings a further benefit: the cover crop protects the soil through winter and reduces erosion.

Organomineral Fertilizer

These are products in which organic material and a mineral nutrient source are combined at the factory, with the content guaranteed on the label. They are a practical middle ground for growers who cannot source farmyard manure; see our organomineral fertilizer article for the detail.

Common Mistakes

1. Using unrotted manure. The costliest mistake: a year later you are fighting weeds.
2. Heaping manure at the trunk. The fine roots are not there, and root collar rot becomes a risk.
3. Leaving it on the surface. Uncovered manure loses nitrogen to the air and washes away with rain.
4. Applying every year. Unnecessary cost and salt build-up.
5. Cutting mineral fertilizer. Farmyard manure does not cover the season’s nitrogen demand.
6. Applying lime, phosphorus fertilizer and manure at once. Spread the operations across the calendar.
7. Leaving the heap out in the rain. A large share of the nutrients drains away.
8. Setting a rate without an analysis. In a soil already adequate in organic matter, extra application is money lost.

Summary

• Organic matter is what keeps applied fertilizer in the soil — critical on sloping, rainy land
• Regional soils are generally of medium organic matter status, but orchards differ enormously
• Manure taken into the orchard must be well rotted
• The application window is November–March; a 30–40 cm band under the canopy projection, hoed in the same day
• The amount is set by soil analysis plus manure analysis; the general reference is 25–30 kg per bush, every 3–4 years
• Do not apply at the same time as lime or phosphorus fertilizer
• Where farmyard manure is unavailable, husk compost is a strong alternative (1.0 t/da gave the best result in the trial)

For the full annual fertilizer calendar see Hazelnut Fertilization Programme, and for sampling and report reading see the Soil Analysis Guide. Our articles on liming, which complements organic matter on acid soils, and on the chlorine-free potassium source potassium sulfate (0-0-51) continue this subject.

📚 Hazelnut Research Station - Fertilization in Hazelnut (2013) 📚 Bayburt Provincial Directorate of Agriculture and Forestry - Storage and Application of Barn Manure 📚 Yavuzkılıç & Gülser (2024) - Journal of Soil Science and Plant Nutrition 📚 Karadeniz & Özkutlu (2023) - Academic Journal of Agriculture 📚 Samsun Provincial Directorate of Agriculture and Forestry - Hazelnut Husk Compost