**1. Introduction**

Tillage is one of the most fundamental practices in agriculture, used to prepare soil for planting, control weeds, manage crop residues, and incorporate amendments. However, excessive and inappropriate tillage can lead to a range of issues that degrade soil health over time. Conventional intensive tillage using implements like moldboard plows and heavy disk harrows can cause serious soil degradation through compaction, erosion, loss of soil organic matter, disruption of soil structure, and depletion of soil nutrients [1, 2]. This decline in soil health under conventional tillage regimes has raised concerns about the long-term sustainability and productivity of farmland under crop production.

In response, there has been a strong push in recent decades to reduce overall tillage intensity and adopt conservation tillage systems that retain protective crop residue cover. However, it is increasingly recognized that eliminating tillage entirely may not be optimal or practical in all cropping systems and soil conditions. Some degree of strategic tillage may provide benefits by disrupting compacted layers, incorporating amendments, managing heavy residue loads, and creating seedbeds for adequate plant stands [3, 4]. The goal of strategic tillage is to balance the need for tillage with the need to protect soil health in a planned, precision approach.

Strategic tillage can be defined as the targeted, occasional use of tillage implements in specifically defined locations, depths, and times to address priority limiting factors while minimizing disturbance of the soil [4, 5]. Unlike routine conventional tillage over entire fields, strategic tillage is applied only where evidence indicates it is necessary. For example, deep tillage may be used to shatter compacted subsoil layers that limit root growth and water infiltration, while shallow zone tillage could incorporate surface-applied fertilizers or break up crusted soils that are prone to poor seedling emergence. The type, timing, frequency, and intensity of strategic tillage varies based on the cropping system context, soil conditions, climate patterns, and specific production goals. Overall, the mindset shifts from a "more tillage is better" approach to using minimal, strategic tillage only as needed to accomplish the intended soil improvements and agronomic benefits.

Multiple studies have now documented that strategic tillage systems can provide equivalent or greater crop yields compared to conventionally tilled soils, while building soil health and retaining many of the environmental advantages of no-till systems [3, 4, 6]. Importantly, the benefits of strategic tillage may be most pronounced in certain soil types and cropping systems. For example, heavy clay soils that are prone to compaction may benefit from occasional deep loosening to improve internal soil drainage and root penetration [7]. Strategic shallow tillage can also help mitigate some challenges faced in long-term no-till systems, such as nutrient stratification, cool wet seedbeds, and heavy residue loads. However, improper implementation of strategic tillage, such as too frequent or aggressive use, could certainly negate benefits and accelerate soil degradation. Overall, evidence to date suggests strategic tillage may offer a useful integration of conventional and no-till approaches to balance multiple soil and agronomic needs, but site-specific conditions must guide appropriate application.

One major goal and purported benefit of strategic tillage is improving overall soil health, which encompasses the chemical, physical, and biological properties that drive soil function and productivity [8]. Soil health degradation associated with intensive tillage is extensive, including loss of soil organic matter, disruption of soil structure, reduced water infiltration, increased compaction, greater erosion, and decreases in biological diversity and activity in the soil food web [1, 9, 10]. Strategic tillage aims to minimize these detrimental effects while still utilizing tillage where evidence shows that it can rectify specific limitations. For example, occasional deep tillage in compacted subsoil zones may improve soil structure and water movement, increase rooting depth, stimulate microbial activity, and improve soil carbon storage while only impacting a small portion of the soil profile [3, 11]. Integrating strategic tillage with practices like cover crops, rotations, and reduced surface disturbance may support many components of soil health while targeting the most critical soil limitations [12].

Soil nutrient dynamics are a key aspect of soil health that may be impacted by strategic tillage implementations. Nutrients like nitrogen and phosphorus are essential
