Equine hoof problems are a major source of concern for horse owners. Hoof issues can lead to lameness and unsoundness, causing discomfort for the horse and potentially leading to early retirement.

In one study, 85% of horses were observed to have at least one form of hoof disorder when examined during regular hoof trimming. [7] In this study, 95.6% of horses were either stalled or housed in small paddocks, which can affect hoof pathology. [7]

Thrush was the most common hoof disease, followed by hoof wall cracks, growth rings, bruising, white line disease and laminitis.

The equine hoof is comprised of multiple structures and tissues that function in collaboration with each other to enable movement of the foot.

Multiple factors including trimming and shoeing practices, environmental conditions, nutritional status, and metabolic health affect the quality and integrity of the equine hoof.

Many hoof problems are preventable with a good nutrition plan and proper equine management practices. In this article, we will review seven common hoof issues in horses and discuss ways to help keep your horse’s hooves healthy.

To support your horse’s hoof health, submit their information online for a complementary review by our equine nutritionists.

Anatomy of the Horse’s Hoof

The outermost layer of the hoof structure is comprised of a hard wall that protects the inner tissues including the laminae (laminar layers) of the foot.

The white line is located between the hoof wall and the sole of the foot and represents the visible part of the laminar layers within the equine foot.

The insensitive laminar layers of the hoof connect to the inside face of the hoof wall. The sensitive laminar layers are the innermost layers of the laminae. They are filled with blood vessels and connect to the coffin bone, the foundation of the hoof.

Here is a brief overview of the external and internal structures of the hoof:

Healthy Horse Hoof Anatomy
Equine Hoof Anatomy Graphic

Common Hoof Problems in Horses

The equine hoof is vulnerable to a multitude of problems ranging from minor to life-threatening. Some of the most common problems that can affect the equine hoof include:

  • Abscesses
  • Thrush and other infections
  • Septic arthritis (joint infection)
  • Hoof bruises, punctures, and corns
  • Hoof wall cracks
  • White Line Disease (Seedy toe) or white line widening
  • Laminitis
  • Founder
  • Navicular Syndrome (Palmar Hoof Syndrome)
  • Bone cysts
  • Fractures
  • Pedal osteitis
  • Cankers or overgrowths
  • Contracted heels
  • Keratoma
  • Frog cancer

Below we explain seven of these common hoof problems in horses in further detail.

1) Abscess

A common cause of sudden and severe lameness, a hoof abscess develops when bacterial or fungal organisms enter the structure through a wound or opening and cause a subsequent infection in the inner tissues. [1][2][3]

The invading microorganisms generate purulent exudate which causes pressure to increase inside the hoof, resulting in extreme pain and lameness in the horse.

Hoof Abscess in Horses

Hoof abscesses are most likely to occur during the wettest seasons of the year including the spring and winter, although they can occur at any time. All horses can be affected by hoof abscesses.

Typical symptoms associated with a hoof abscess include variable degrees of lameness depending on the severity of the infection, a pounding digital pulse, and the presence of heat and swelling in the foot. [4] Not all of these symptoms need to be present to suspect a hoof abscess.

If left untreated, the symptoms of an abscess can worsen and potentially lead to permanent damage of the foot or cause sepsis of important internal structures. [5]

Diagnosis & Treatment

Hoof abscesses are diagnosed by visually inspecting the affected hoof and using hoof testers to determine the sites at which pain is present. In some cases, taking radiographs of the hoof is necessary to locate the site of the abscess within the foot. [6]

A critical factor in treating all hoof abscesses is ensuring proper drainage from the site of the abscess in the hoof. [2] A veterinarian and or farrier may need to be involved in the treatment of abscesses where proper drainage is not present.

Poultices and drawing ointments such as ichthammol are commonly used to promote drainage from a hoof abscess. Once drainage occurs, affected horses typically experience significant pain relief.

During the healing process, an antiseptic treatment such as betadine or two percent iodine should be applied to the drainage tract of a hoof abscess. Medicated putty may also be used within the drainage tract to ensure microorganisms cannot re-enter the hoof.

Horses being treated for an abscess should be housed in a clean, dry area, such as a well-bedded stall or small paddock. During treatment, bandages should be removed and changed daily.

An abscess is considered healed after the drainage tract dries out and the affected tissues have healed over the opening of the tract. Only after abscess healing is complete and affected horses become fully sound, should shoes be applied to their hooves. If shoes are absolutely necessary, a shoe with a hospital plate can be applied to allow access to the abscessed area.

Horses with a mild infection due to a hoof abscess may be able to return to work in less than a week following treatment. However, abscesses involving deep infections can take several weeks or even months to resolve.

2) Thrush

A relatively common infection that affects the center and grooves (sulci) of the frog of the equine hoof, thrush is caused by bacterial and or fungal organisms. A Dutch study of 942 randomly selected horses found that 45% had thrush. [7]

Among the different species of bacteria that can cause a thrush infection in horses, Fusobacterium necrophorum is the most frequently involved. [8] More important than the type of organism causing the infection, however, is the situation that sets the sulcus up for the infection to occur.

Thrush infection is more likely to occur in the hind feet of horses stalled in moist, damp, and unclean conditions.

Some horses are more prone to contracting the infection if they have a long heel conformation that promotes deep, narrow frog sulci and are exposed to the contributing environmental conditions.

Symptoms of thrush include a black and foul-smelling discharge emanating from the affected areas of the frog. Horses with thrush may also display pain when pressure is applied to these areas.

Treatment

Thrush is treated by removing necrotic tissue from the hoof, a process completed by a farrier or veterinarian. The affected hooves should be cleaned daily with a diluted iodine solution or other antifungal or antibacterial product.

If granulation tissue or sensitive structure of the hoof are exposed after debridement of the necrotic tissue, astringents should be avoided. Your veterinarian can prescribe metronidazole, which can be made into a paste and packed into the area. A hoof bandage is applied and changed daily until the area is healed over.

To prevent and help treat thrush, horses should be stabled in a dry and clean environment. A tetanus vaccine should be administered to horses that are not up to date on their vaccination against the disease.

Horses treated for thrush typically recover within 7 to 14 days unless there are complications involving the deeper tissues of the hoof being affected.

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3) Hoof Bruise

A hoof bruise occurs when there is hemorrhaging within the hoof tissue caused by acute trauma to the hoof. [9][10] Improper shoeing or farrier work and blunt trauma can promote the development of hoof bruises.

The most common signs of a hoof bruise include visible patches of discoloration on the sole or wall of the hoof. Depending on the degree of bruising in the hoof, some horses may show slight sensitivity whereas others may be lame.

Rest is needed for horses to heal from a bruised hoof. Using protective cushioning on the foot from shoes, pads, boots, or wraps may help horses feel more comfortable during the healing process.

Occasionally, a hoof bruise may create favorable circumstances for an abscess to develop. The owner should keep this in mind if the lameness persists or if the condition suddenly deteriorates.

4) White Line Disease

A disease that destroys the two inner tissue layers of the hoof wall that are covered by the hard outer layer, White Line Disease results from bacterial and fungal invasion into the hoof. [11][12]

These microbes invade the tissues of the hoof wall through a separation or crack and subsequently cause an infection.

White Line Disease in Horses

Factors believed to promote the development of white line disease in horses include living in conditions that are excessively wet or dry and having hoof capsule distortions such as long toes, under-run heels, a club foot, or sheared heels.

White line disease can develop in one or more feet of the horse. Horses with mild white line disease may not exhibit lameness, whereas those with severe damage to their hoof wall may suffer laminitis and coffin bone sinking and or rotation.

A powdery hoof wall without a solid junction between each layer is commonly present in horses with white line disease. When tapped with a hammer, an affected hoof may produce a hollow sound.

Diagnosis & Treatment

Veterinary advice should be sought to determine the extent of damage caused by white line disease in affected horses. X-rays may be used to evaluate the problem and aid in developing an appropriate treatment plan.

Treatment of white line disease typically requires hoof-wall resection by a skilled farrier. [11][12] The farrier cuts away each of the three layers of the hoof wall to remove the infected parts of the hoof. Once resected, the hoof will require support with a bar or other form of therapeutic shoe.

This is a complicated procedure that should only be conducted by farriers or veterinarians trained in advanced podiatry.

During the healing process, a farrier will debride the affected area regularly. A resected hoof will take several months to a year to grow out and must be kept as clean and dry as possible to prevent the infection from recurring.

5) Laminitis

A painful condition, laminitis occurs when the interlocking laminae which connect the coffin bone to the outer hoof wall become elongated and weakened or lose their basal attachment. [13][14]

This condition can range from mild to severe and potentially lead to founder which involves laminar damage and coffin bone rotation and or sinking. [15][16][17]

 
Healthy vs Laminitic Horse Hoof
 

The most common cause of laminitis in horses is abnormally high insulin due to grain overload or sudden access to lush pasture. Horses most at risk for the condition include those with endocrine disorders including Equine Metabolic Syndrome and PPID (Equine Cushing’s disease). [18][19][20]

Horses with one of these predisposing diseases can have a laminitic episode when they are not on any grain or pasture if the hydrolyzable carbohydrate (HC) portion of their diet is 10% or higher. Hydrolyzable carbohydrate is the portion of NSC that is digestible in the small intestine and and contributes to the insulin response. Research has shown that the only risk factor for pasture-associated laminitis is elevated insulin. [41]

Laminitis can also occur due to other causes, including:

  • During illness, such as colic, salmonella infection, Potomac Horse Fever, Bastard Strangles or retained placenta. This condition is referred to as septic-associated laminitis. [18]
  • During a non-weight-bearing lameness that induces stressful forces in one or more hooves of the weight-bearing limbs. This condition is referred to as support limb laminitis. [18]
  • Exposure to black walnut hull shavings [21]
  • Hoary alyssum ingestion in hay or at pasture
  • Grain overload
  • Pregnancy induced insulin resistance

Symptoms of laminitis include:

  • Softening of the coronet band
  • Heat in the hooves
  • Increased digital pulse (pulses on the inside of the fetlock)
  • Reluctance to move
  • Reluctance to make sharp turns
  • “Sawhorse” stance or weight shifting to the hindquarters with hind legs tucked underneath them similar to a horse with hock pain
  • Positive pain test when hoof testers are applied
  • Muscular tension in the shoulders, back and hindquarters

Treatment

Horses suspected of having laminitis should be evaluated by a veterinarian as soon as possible. With prompt treatment, lasting damage to the hoof structure may be prevented and many horses can recover.

Treatment of laminitis involves removing the underlying cause of the condition. For example, dietary changes must be implemented immediately to reduce insulin and underlying infection or illness must be treated. [22]

A realigning trim with boots and pads or therapeutic shoeing, the use of pain medication, soft and deep bedding, and cold therapy are common strategies that are used to support horses healing from laminitis. [23]

Anti-inflammatory drugs, such as NSAIDs, are of limited use in laminitis caused by high insulin rather than a systemic inflammatory response because inflammation is only part of the cleanup response, not the cause. [42]

6) Founder

Damage to the laminar connection between the hoof wall and the coffin bone that results in rotation and/or sinking of the coffin bone is referred to as founder.
[17][16] This condition can have a sudden onset or occur slowly over time.

Founder is very painful for the horse and can result in a permanently altered hoof structure. Multiple factors can contribute to the development of founder. [16]

Founder is an extension of laminitis and the same causes listed above apply for founder. Metabolic disorders involving abnormally high insulin are the most common cause. Pasture-associated laminitis falls into this category.

Another scenario that can cause laminitis or found is where horses accidentally gain access to an unlimited supply of grain. This overwhelms the digestive capacity of the small intestine. The excess then spills over into the cecum and hindgut, where fermentation causes enough acidity to damage the intestinal lining. [16]

If the intestinal lining is compromised, toxins can enter the peripheral blood supply and cause damage to the laminae.

Similarly, acute illnesses such as colic and diarrhea, which cause inflammation in the small intestine, increase a horse’s risk of founder due to the presence of endotoxins in their body. [16]

Mares that retain their placenta are also at risk for the founder due to increased levels of endotoxin exposure. [16] A placenta is considered retained if it not passed within three hours of foaling and action must taken to help the placenta pass.

Horses with non-weight-bearing lameness may develop founder if the laminae in the hooves of their supporting limbs are overloaded. [16]

Horses with metabolic issues such as Cushing’s/PPID and EMS have a higher risk of founder. [25][26] This is related to higher levels of insulin which cause lamellar lengthening and weakening with potential failure and progression to founder.

Horses with founder may show a range of signs of distress and discomfort. The most common clinical symptoms include:

  • Sudden lameness
  • Resistance to moving
  • Feeling a strong digital pulse and heat in the foot
  • Shifting weight back and forth
  • Standing with the legs camped out in front of the body or with all four legs under the body
  • Laying down more frequently

Diagnosis & Treatment

An accurate diagnosis of the condition requires clinical and radiographical examinations of the hooves by a veterinarian. The sooner treatment is started, the better the chance that affected horses will recover.

Prevention and treatment of founder requires addressing the underlying causes of the condition such as improper diet and metabolic issues. Horses with founder are commonly administered non-steroidal anti-inflammatory drugs (NSAIDs) to relieve pain and inflammation.

However, these drugs are minimally effective in metabolic cases because the root cause is not related to inflammation. Getting insulin under control is the most important part of their therapy. Use of NSAIDs for a few days is reasonable during the cleanup process.

Different analgesics, such as tramadol, may be more effective.

Corrective trimming and shoeing are critical for horses that have foundered. Some horses may also benefit from cold water therapy to reduce inflammation and slow the progression of laminitis in their affected feet. However, cold is likely contraindicated in metabolic cases as they already have impaired circulation.

Lifelong diligent attention to farrier care is required in these horses. Trims are often recommended every four weeks.

Navicular syndrome, also referred to as navicular disease or podotrochlear syndrome typically occurs in the forelimbs and affects the podo­trochlear apparatus (PTA) of the equine foot. [27][28][29][30]

The PTA is comprised of multiple structures within the heel of the hoof, including the navicular bone, coffin joint, and ligaments and tendons. [27][31]

Horses affected by navicular syndrome may exhibit a mild to severe degree of lameness, changes in their gait, and a general reduction in performance. Commonly, both feet are affected, which can make it harder to detect lameness. Indications such as increased tripping, toe-first landing, contracted heels, or a shortened stride may be the only noticeable signs.

In affected horses, the rear portion of the foot can undergo a range of changes due to the condition.

Navicular syndrome may involve abnormal bone remodeling processes in the navicular bone and the development of inflammation, lesions, and adhesions in the DDFT. [27] The distal interphalangeal (DIP) joint and the navicular bursa may also be affected by inflammation and are typically involved before the bone. [27]

Damage to the impar ligament, between the distal phalynx (coffin bone) and the navicular bone, can also be a cause of pain.

Because navicular syndrome typically affects multiple structures in the foot, it is believed there are several factors that can precipitate the development of the condition.

Horses are more likely to have the condition if they:

  • Have genetic factors that contribute to the existence of poor nutrient channels in their navicular bone.
  • Are over ten years of age
  • Have a weight-to-height ratio of 3.45 or higher
  • Are born with a divided navicular bone
  • Have suffered an injury that results in poor blood supply to the rear of the foot
  • Have small feet for their height and weight
  • Have a long toe and underrun heel hoof conformation

Diagnosis & Treatment

Diagnosing navicular syndrome requires a veterinary clinical evaluation that includes diagnostic analgesia and radiographic imaging. [33] Magnetic Resonance Imaging (MRI) may be needed as the soft tissues of the foot cannot be visualized with a regular radiograph.

There is no cure for navicular syndrome. However, corrective trimming and shoeing, medications, and non-surgical and surgical interventions are commonly employed as treatments for the condition. [34]

These interventions can significantly improve the horse’s mobility. Treatments vary depending on the results of veterinary exams and which structures are affected the most.

Key Tips for Healthy Hooves

Nutrition: Feed a high-quality mineral/vitamin supplement

To grow and maintain healthy hooves, horses require a balanced diet that provides adequate amounts of key vitamins and minerals. [35][36][37][38][39][40]

Some of the most important nutrients known to support hoof integrity include biotin, copper, selenium, and zinc. For a 500kg horse at maintenance, optimal amounts of each of these nutrients are as follows:

  • Biotin: 20mg per day
  • Zinc: 400mg per day
  • Copper: 100 mg per day
  • Selenium: 2mg per day

It is recommended to feed a mineral and vitamin supplement that provides organic trace minerals, which are better absorbed and utilized by the body compared to inorganic trace minerals.

Mad Barn’s Omneity mineral and vitamin supplement provides all of the nutrients required to grow out robust, healthy hooves. It balances the majority of forage and grain-based diets and is designed to correct for the most common nutrient deficiencies that can impair hoof growth.

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  • Our best-selling equine vitamin

Nutrition: Ensure amino acid supply is adequate

Methionine is a sulfur-containing amino acid which is the precursor for cysteine. Sulfur-sulfur bonds between these amino acids produce the strength and structural integrity of the hoof wall.

Since the institution of strict pollution control, sulfur deposition on soil has greatly decreased. [43] As a result, plants have less ability to manufacture these critical amino acids and deficiencies become more likely.

Common manifestations are poor muscular development, muscle soreness, poor performance and poor hoof quality. Mad Barn’s DL-Methionine can be used to supplement methionine.

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  • Hoof & coat quality
  • Maintain healthy joints
  • Exercise recovery
  • Antioxidant status

Hoof Care: Maintain a regular farrier schedule

Keep your horse’s hooves well maintained on a regular trimming/shoeing schedule of 4 to 6 weeks. Shorter intervals between farrier sessions are better than longer ones and will make it more likely that hoof issues are caught early.

Regular trimming can help prevent the growth of long hoof walls and hoof imbalances which promote stress and strain on the hoof capsule, soft tissues, and ligaments. Regular farrier work is critical to guard against the development of hoof problems.

Paddock Management: Avoid wet areas your horse’s turnout space

Ensure that the turnout area where your horse spends the most time is dry.

Consider laying down a gravel base and filling it with round, pea-sized gravel to a depth of approximately 4 inches to create an area in your pasture that can drain away excess moisture.

When wet conditions cannot be avoided, ensure you clean and dry feet out daily.

Summary

Hoof problems in horses are an extremely common occurrence, affecting 85% of horses in one study.

While most hoof issues are mild, if left untreated they can worsen over time and lead to lameness. Problems with your horse’s hooves such as laminitis can also signal systemic health concerns that need to be addressed.

Vigilance, regular farrier care and good management practices are all important to support hoof health. Your horse’s diet also plays a critical role in supplying the nutrients required to grow healthy hoof tissue.

Is your horse affected by hoof problems? Submit their diet online for analysis by our equine nutritionists to identify deficiencies or imbalances that might be impairing hoof growth.

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References

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  3. Cuomo, F. Horse Hoof Abscesses. University of Minnesota Extension. 2021.
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  11. Redding, W. and O’Grady, S. Nonseptic diseases associated with the hoof complex: keratoma, white line disease, canker, and neoplasia. Vet Clin North Am Equine Pract. 2012.
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  13. What is Laminitis? Royal Veterinary College. University of London. 2021.
  14. Fraley, Brian, DVM. Founder vs. Laminitis. The Horse. August 5 2020.
  15. Laminitis FAQ. The Laminitis Site. 2019.
  16. Laminitis: Prevention & Treatment. AAEP. 2021.
  17. Young, A. Laminitis. UC Davis. 2020.
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  19. Geor, R.J. Metabolic Predispositions to Laminitis in Horses and Ponies: Obesity, Insulin Resistance and Metabolic Syndromes. J Equine Vet Sci. 2008.
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  21. Horses and Black Walnut Shavings. OMAFRA. 2021.
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  34. Bell, B.T.L. Surgical treatment of navicular syndrome in the horse using navicular suspensory desmotomy. New Zealand Veterinary Journal. 1996.
  35. Comben, N. et al. Clinical observations on the response of equine hoof defects to dietary supplementation with biotin. Vet Rec. 1984.
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  39. Buffa, Eugene et al. Effect of dietary biotin supplement on equine hoof horn growth rate and hardness. Equine Vet J. 1992.
  40. Mills, CF. Dietary interactions involving the trace elements. Annu Rev Nutr.
  41. Menzies-Gow, N.J. et al. Prospective cohort study evaluating risk factors for the development of pasture-associated laminitis in the United Kingdom. Equine Vet J. 2017.
  42. Patterson-Kane, J.C. et al. Paradigm shifts in understanding equine laminitis. Vet J. 2018.
  43. Feinberg, A. et al. Reductions in the deposition of sulfur and selenium to agricultural soils pose risk of future nutrient deficiencies. Nature Comm Earth Environ. 2021.